Bootloader Locking, Unlocking, S-On, S-Off - Questions and Answers - HTC One Max

Source @Koush (Original Article)
Source @HTCDev (Original Article)
Bootloader Locking, Unlocking, S-On, S-Off - Questions and Answers
It seems this is confusion in the community about what S-OFF is and why it's needed on some phones but not others. I endevour to educate and explain why some HTC devices need S-OFF while others do not to Flash Roms and recovery images.
[Q] What does S-ON/S-OFF mean? Is it on all phones?
[A] This is Manufacturer specific to HTC branded devices ONLY. S-On and S-Off means Security On/Security Off. HTC devices are set to S-ON by default for a good reason. There are partitions such as hboot which controls access to all other partitions which if made fully accessible could compromise security and very possibly allow for irreversible changes that could render your device inoperable. For warranty and device support purposes alone it would be to your benefit to keep Security-ON. Another partition that is secured is the radio. It is not advisable to alter or customize the radio and most custom roms will not need to. The radios are fine tuned to the specific carrier(s) they are designed to support and with the specifications as prescribed by law. Moreover altering them may not only also cause irreparable damage to your device but it could very well interfere with the normal communications possibly affecting other devices.
[Q] What does Unlock mean in the bootloader flag?
[A] What is meant by unlocking the bootloader is that certain partitions are unlocked to provide write access without turning device security off for all partitions. Specifically: Kernel, system and recovery partitions are allowed to be modified. There are more partitions (e.g. the radio and hboot) but these are the minimal necessary to overwrite a default stock rom with a custom built Android based rom.
[Q] Then why do Devs ask for S-OFF when flashing a Rom?
[A] Some carriers lock down the ability to Unlocked the partitions. For example US customers of Verizon are unable to use HTCDev to unlock their devices to access the needed partitions for Custom Rom and Recovery writing. In this Case S-OFF fixes this issue but also unlocks ALL partitions for writing. A Verizon phone with S-OFF will have the ability to now write to the Recovery and Boot partitions.
Devs ask for S-OFF for multiple reasons:
1. So that Devices Restricted by HTCDev whom normally can't get write access to the Boot and Recovery Paritions can use there ROM
2. Because forum behavior made S-Off appear to be needed
3. Laziness and/or ignorance (not trying to be rude)
[Q] So do I really need S-OFF to install ROMS or Recovery Images?
[A] Yes, If you have a HTCDev Restricted Device which will not allow you to use a Unlock Token you will need to S-OFF in order to write to your boot/system/Recovery partitions. NO, if you have a devices that can be unlocked using HTCDev Token to Unlock your device.
[Q] So Unlocking my devices has nothing to do with S-ON/S-OFF?
[A] A tricky question. Yes Unlocking a None Carrier restricted device with HTC Dev has Nothing to do with the Security of the Device from the S-OFF/S-ON perspective. If your on a Carrier Restricted HTCDev devices (I.E. Verizon HTC One Max) then in order to Write to the Partitions you need to you will need to be S-OFF as that is the only way to Unlock the bootloader.
[Q] So why do I need to Change my Bootloader Flag to get some things working?
[A] The short answer is that some hardware in the HTC Phones are told to look into the Security Partition to determine if the phone is Locked or Unlocked for Development. As an example on the HTC One Max the Fingerprint Reader will be disabled if the Bootloader Flag is set to "Unlocked" but function if the Flag is Set to "Locked". When your Bootloader is Flagged "Locked" the partitions are not accessible and will prevent Recovery and Boot Partition Modifications.
[Q] What if I want to return my device for warranty work how can I return it to S-ON and Locked Status?
[A] You will need to find your Model Phones RUU and Restore your phone to it original stock state. The RUU is used to restore a device to its Factory State. See the Question below about S-ON.
[Q] I would like to know if its still possible to achieve s-on after you have turned it off specially using the Rumrunner tool as I am Verizon device?
[A] Consumers that use Rumrunner to S-OFF will have the option of turning Device Security ON again. This typically is not a deal breaker for Warranty repairs if you restore the device software (Recovery, Room) back to it's default stock state and flag the bootloader Locked again as some devices are shipped S-OFF. It has been accomplished on the HTC One by running a command in Fastboot mode.
HTC One users achieve S-ON again by running this command with fastboot. I have not yet confirmed it works on the HTC One Max. (Note: If you are trying to return to a out of the box state use your device's RUU after S-ON to restore the Recovery, Kernel and Rom to Stock with a Encrypted/Signed RUU then run the command below) (If you want to test and report back on the HTC One Max please let us know.
fastboot oem writesecureflag 3
Click to expand...
Click to collapse
[Q] What is the difference between an Encrypted RUU vs Decrypted RUU?
[A] A Encrypted RUU is a RUU file that has been signed by HTC (Carrier or Country). Encrypted RUU's can be run on S-ON or S-OFF devices to restore the device. A Decrypted RUU is a RUU that has had the signature stripped(in case of JB or older RUU's) and these can be typically ONLY run on S-OFF Devices. (Be careful to use the RUU for your device as these are hardware specific)
In conclusion:
S-OFF/S-ON is conditional based on your HTC device and carrier restrictions. If you are not able to unlock your partitions with HTCDev due to Carrier restrictions or country restrictions then S-OFF is you alternative.
If you can unlock your phones bootloader then you can flash kernels, roms and recovery images with S-ON. S-OFF is ONLY needed on devices that want full Partition access and/or HTCDev will not allow to unlock.
Do you you have a question? Reply with your question on this thread about S-ON/S-OFF/Bootloader Security. NOTE: This is not a General Question Thread.
P.S.
Please remember that unlocking your bootloader may void all or parts of your warranty and your device may not function as intended by HTC. Unlocking the bootloader is for development purposes only.

DeadPhoenix said:
[Q] So why do I need to Change my Bootloader Flag to get some things working?
[A] The short answer is that some hardware in the HTC Phones are told to look into the Security Partition to determine if the phone is Locked or Unlocked for Development. As an example on the HTC One Max the Fingerprint Reader will be disabled if the Bootloader Flag is set to "Unlocked" but function if the Flag is Set to "Locked". When your Bootloader is Flagged "Locked" the partitions are not accessible and will prevent Recovery and Boot Partition Modifications.
Click to expand...
Click to collapse
Thank you for researching and providing answers.

This is very informative, sure would be nice if us on Verizon could just unlock instead of having to go s-off. I came from the Rezound where we could just unlock, but oh well such is the way it goes.

mods should sticky this thread, as it answers alot of newbie questions..

great write up,not much to add at all
on carrier restricted phones,s off is neccessary to unlock the bootloader,but the device does not need to remain s-off. one could even legitimately unlock via htcdevs website if the cid or mid is changed after achieving s off. after htcdev unlock is achieved,you techincally could turn the radio secure flag back on,but please dont do it. with a lack of signed ruus,doing so could leave you in an unrecoverable jam. i just wanted to clarify that the the functionality of the device itself does not need the secure flag to be off.
while it may not be "needed",it is my personal opinion s-off is better. at least as long as youre a responsible individual who is capable of learning,and exercising good judgment as to what to flash and why,and is able to check the integrity of any downloaded files that could potentially leave the phone unusable(for example,anything that contains a bootloader,as a bad bootloader flash will leave you unrecoverably bricked)
being s off offers many safety advantages:
-you can flash an unsigned ruu to get your device "unbricked"
-you can install older ruus if needed
-you can install a "patched" or engnieering hboot to gain the use of extra fastboot commands
-it lets you dump and modifiy partitions you couldnt with an s on device
not to mention,it lets you eliminate the telltale relocked watermark that lets htc or your carrier know that you have messed with your phone
its also an awsome safety net for those of us who run stock in order to capture OTA packages that provide upgrade firmware and provide rom devs with files to create new custom roms,and update their current versions.
sure staying s on techncally will keep you from accidentally overwriting your bootloader with the "lets golf" .apk, if you find yourself in a bind with a non booting phone and no signed ruu to run,being s on offers no advantage whatsoever.

Scotty, so what you are saying is even if I am S-OFF I can still get the OTA updates from Verizon, like hopefully the Kit Kat update? I was wondering because I was wanting to try the Viper rom as I loved that on my Rezound but didn't want to miss the official Kit Kat.

JBS976 said:
Scotty, so what you are saying is even if I am S-OFF I can still get the OTA updates from Verizon, like hopefully the Kit Kat update? I was wondering because I was wanting to try the Viper rom as I loved that on my Rezound but didn't want to miss the official Kit Kat.
Click to expand...
Click to collapse
The Function of Device Security (S-OFF and S-ON) is to Lock or unlock ALL partitions.
OTA updates are signed by the carrier. So Running Stock Roms will allow the Stock updates from Verizon to work. If your running a Custom Rom then this is dependent on the Rom creator. In most cases OTA updates are not delivered to devices running Custom Roms.

JBS976 said:
Scotty, so what you are saying is even if I am S-OFF I can still get the OTA updates from Verizon, like hopefully the Kit Kat update? I was wondering because I was wanting to try the Viper rom as I loved that on my Rezound but didn't want to miss the official Kit Kat.
Click to expand...
Click to collapse
dont worry about getting the kit kat update; once its actually released, the great dev's here will make it work for our rooted/unlocked phones!

Thank you for your reply DeadPhoenix, I am mostly concerned with getting the official updates from VZW/HTC. I am understanding that if I just use Rumrunner to S-OFF and stay completely stock I will still receive them, now what about putting TWRP on? Will that affect the ability to receive the updates? Thanks again for answering my questions as I'm sure you tire of getting these noob type questions, but I really appreciate the time you all put into this stuff and taking the time to answer.

generally speaking, you can NOT get OTA updates when you have a custom recovery installed..

wase4711 said:
generally speaking, you can NOT get OTA updates when you have a custom recovery installed..
Click to expand...
Click to collapse
Correct. An OTA update relies on the fact that you have a stock Recovery installed as that is the expected delivery method for their scripting.

DeadPhoenix said:
Correct. An OTA update relies on the fact that you have a stock Recovery installed as that is the expected delivery method for their scripting.
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Click to collapse
thanks teacher, I didnt know this was a quiz! :cyclops:

ok.. so I now fully understand what an s-off and s-on mean, however, I would like to know if its still possible to achieve s-on after you have turned it off specially using the rumrunner tool as I am verizon device?
is there a security risk if I kept s-off and have restored back to Verizon's RUU and have locked the bootloader?

afsandiego said:
ok.. so I now fully understand what an s-off and s-on mean, however, I would like to know if its still possible to achieve s-on after you have turned it off specially using the rumrunner tool as I am verizon device?
is there a security risk if I kept s-off and have restored back to Verizon's RUU and have locked the bootloader?
Click to expand...
Click to collapse
Thank you for asking this. These are exactly the questions I know exist out there and would like truly "knowledgeable" people to answer.

afsandiego said:
ok.. so I now fully understand what an s-off and s-on mean, however, I would like to know if its still possible to achieve s-on after you have turned it off specially using the rumrunner tool as I am verizon device?
is there a security risk if I kept s-off and have restored back to Verizon's RUU and have locked the bootloader?
Click to expand...
Click to collapse
From the research I have done with Android/Linux Partition Table Devs and HTCDev directly I derived the following:
The RUU just restores the software to the Factory state. S-OFF is desired however you can use the fastboot command to turn it on in theory. You can S-ON again however this isn't usually a deal breaker for warranty repair as long as you restore the kernel, recovery and Rom to stock. But your mileage may vary with HTC.
Thank you for your question.

Sorry but I believe flashing an encrypted ruu will actually s-on your device. The ruu's we have are decrypted and likely have been provided as they are so that no one fully s-on locks their device again
* fastboot oem writesecureflag 3 will s-on after flashing full stock ruu. Do not attempt if you do not know what you are doing!
As always I am happy to be corrected. Just really want the complete correct information out there, not just as it relates to our device.
---------- Post added at 02:37 PM ---------- Previous post was at 02:27 PM ----------
My apologies if my response seems like an ambush as I posted something earlier. I was just happy others were taking an interest then just did not have a chance to get back to this until a moment ago.

Jiggity Janx said:
Sorry but I believe flashing an encrypted ruu will actually s-on your device. The ruu's we have are decrypted and likely have been provided as they are so that no one fully s-on locks their device again
* fastboot oem writesecureflag 3 will s-on after flashing full stock ruu. Do not attempt if you do not know what you are doing!
As always I am happy to be corrected. Just really want the complete correct information out there, not just as it relates to our device.
---------- Post added at 02:37 PM ---------- Previous post was at 02:27 PM ----------
My apologies if my response seems like an ambush as I posted something earlier. I was just happy others were taking an interest then just did not have a chance to get back to this until a moment ago.
Click to expand...
Click to collapse
I will attempt to get this clarified as it seems we are seeing 2 different answers and I want this to be as accurate as possible.

DeadPhoenix said:
I will attempt to get this clarified as it seems we are seeing 2 different answers and I want this to be as accurate as possible.
Click to expand...
Click to collapse
Agreed. Source: http://forum.xda-developers.com/showthread.php?t=2475216

Jiggity Janx said:
Agreed. Source: http://forum.xda-developers.com/showthread.php?t=2475216
Click to expand...
Click to collapse
From the Feedback I have gotten so far. They explicitly state RUU's do not turn S-OFF to S-ON however in the directions you sourced a command is run outside of the RUU to turn it on.
(Still awaiting several replies to queries.)
This Appears to be the fastboot command to run AFTER the RUU has restored but before a normal boot but is Not part of the RUU process itself.
This is also if CID is modified from what I gathered thus far. (Feel free to correct)
fastboot oem writesecureflag 3
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Click to collapse

DeadPhoenix said:
From the Feedback I have gotten so far. They explicitly state RUU's do not turn S-OFF to S-ON however in the directions you sourced a command is run outside of the RUU to turn it on.
(Still awaiting several replies to queries.)
This Appears to be the fastboot command to run AFTER the RUU has restored but before a normal boot but is Not part of the RUU process itself.
This is also if CID is modified from what I gathered thus far. (Feel free to correct)
Click to expand...
Click to collapse
Did you ask 'them' specifically about flashing stock encrypted htc ruu's? I am digging more but believe the encrypted ones have the writesecure flag already set to 3(s-on). Encrypted ruus would be what htc has given manufacturers to install on phones before shipping them to vendors.
Also you would want your device to be completely stock (no changed cid) before using fastboot to s-on. You would use this command after flashing a decrypted (but still completely stock) ruu.

Related

Flash radio after htc unlock?

Hello all, I used the htc unlock method, but I am not able to flash a different radio version.
Does anyone know how to do that?
(Just booting into bootloader does not do the trick like it would normal unlock methods)
Thanks.
Anyone?
Sent from my PG86100 using XDA App
have you tried the commands
adb reboot bootloader
fastboot boot recovery.img
and flashing the radios from fastboot? or FlashimageGUI (which probably will not work for radios)
I have been wondering this myself. I have not heard of any methods that have come up to allow this recently. Same thing goes for splash images as I havent seen any method for those.
I have an idea of how it may be possible though. Perhaps someone else with a bit more knowledge can chime in to let us know if it is possible or not.
Anyhow.
Being officially unlocked I don't believe that ROOT is an issue like it is on an unofficial method. I know typically you would NOT accept an OTA to prevent the loss of ROOT. However, being an officially unlocked device, I am not sure if it matters.
I know that when I unlocked my device I had to manually unlock it, then I installed my recovery, then I simply flashed SU to it. My thought is that you can take the OTA. If the OTA doesn't work, you may have to re-lock the device, then run the OTA. But I believe the OTA would be safe. Once OTA completed, then flash your unlock token again, put recovery back on, then flash SU again.
Or I believe you could also wait for the new RUU instead of an OTA. Put on stock ROM, re-lock, run RUU, re-unlock, install recovery, flash SU.
The problem is that you may not be able to flash back to the previous radio once you are done.
Any thoughts on this?
UPDATE: I recently (like two minutes ago) learned that an RUU will not update a radio. I was under the impression that they did. Since it will not, I guess the RUU method will not work. Still curious about the OTA method though.
From the HTCDev Q and A:
HTCDev said:
Why is my security still on (S-On) after I have unlocked my bootloader?
Your device is shipped with Security on (S-ON) to protect your system software configuration (such as the bootloader, radio, boot, recovery, system and others). After you have unlocked the bootloader, however, you will have lifted the restrictions on boot, recovery and system. This means you can customize boot, recovery and system images on your phone as you desire. You can easily see that you have successfully unlocked the bootloader by looking at the top of the screen when entering the bootloader screen. Security is left on to protect things like the radio, and SIM lock.
Click to expand...
Click to collapse
yousefak said:
From the HTCDev Q and A:
Click to expand...
Click to collapse
Well, yeah. The S stays on to protect the radio.
But the S would be on regardless if you never rooted to begin with, but an OTA would allow the radio to update. So, my thought is that you can potentially take an OTA with the HTC unlock method and get the new radio.
If it were me, I would save my titanium file to my PC (just as a precaution), I would re-lock my device using fastboot oem lock, then I would run the RUU that matches my current software version. This would return me to stock/unrooted. At this point you should be able to accept an OTA. The OTA updates your radio/software/etc. Once you update, flash the unlock token again, then flash the superuser binary back onto the phone. Now, this would be contingent that HTC doesn't go back on their word and they dont push an OTA that prevents you from unlocking the phone.
Now, Ill admit I am not a developer, so I am not an expert, but it is my understanding that once it is unlocked putting root on the phone is pretty straight forward. You don't have to come up with a root method such as revolutionary, etc. It should simply allow Superuser because it is unlocked. If this is not the case, then Ill admit that my thought process is flawed. However, if it is the case, then why not return to stock, take an OTA, unlock, re-root, use titanium? Like I said, may not be able to return to previous radio, but why would you anyhow?
mildlydisturbed said:
have you tried the commands
adb reboot bootloader
fastboot boot recovery.img
and flashing the radios from fastboot?
Click to expand...
Click to collapse
Can someone tell me how exactly to accomplish the above?
I ran these commands and the it said "Installing update..." but the radio remains the same.
Thanks again.

Quick Root Question

I haven't exactly rooted 100 devices before. Most of the root utilities I've used were things like Z4Root where it's one click and done. I've recently become interested in flashing my Incredible 4G LTE. On top of that, I've already rooted my Nexus 7 using instructions like this here.
http://forums.androidcentral.com/ne...ide-factory-image-restore-your-nexus-7-a.html
I'm curious if this guide, being that it's more of a manual way to do it since it involves running several commands (I ran this from my Linux desktop to root my N7) is anything like what it would be to root the Incredible manually, or any device. I guess the only device that would be different would likely be the bootloader step (grouper?) since HTC likely did their's differently than Google with the Nexus 7, no?
Just trying to get more insight on it, as I certainly don't want to brick anything but I'd like to get them done. :good:
It seems to me that we would first need a modified bootloader or /system to attempt to flash, but I doubt "fastboot erase ..." is allowed without dev unlock on the bootloader, and "fastboot flash ..." most likely needs a signed image.
Does anyone with more expertise on this topic have any input?
JaSauders said:
I haven't exactly rooted 100 devices before. Most of the root utilities I've used were things like Z4Root where it's one click and done. I've recently become interested in flashing my Incredible 4G LTE. On top of that, I've already rooted my Nexus 7 using instructions like this here.
http://forums.androidcentral.com/ne...ide-factory-image-restore-your-nexus-7-a.html
I'm curious if this guide, being that it's more of a manual way to do it since it involves running several commands (I ran this from my Linux desktop to root my N7) is anything like what it would be to root the Incredible manually, or any device. I guess the only device that would be different would likely be the bootloader step (grouper?) since HTC likely did their's differently than Google with the Nexus 7, no?
Just trying to get more insight on it, as I certainly don't want to brick anything but I'd like to get them done. :good:
Click to expand...
Click to collapse
What those tools do is use an exploit to write the su and superuser.apk to /system and/or a modified recovery for flashing ROMS and kernels on unlocked bootloader devices.
google has properly patched those exploits as they should as we don't want a malicious app installing Root and hacking data on just anyone's phone.
Some phones with locked bootloaders have had exploits to install custom recovery and/or hacked/leaked bootloaders in order to allow us to use the phone like it was unlocked. HTC fixed this issue with their latest phones.
Their bootloaders now do not run all of the adb commands until unlocked by HTC dev, which limits us a lot. They also made it so that even if we DID manage to find a software exploit and start flashing stuff, the locked bootloader would know, via a signature check, that something was modified... and refuse to boot (Bricked Phone).
HTC Dev unlock is not true unlock either. We still can't modify the HBOOT w/o triggering it to brick the phone. An unlocked HTC bootloader limits changing the kernel to HBOOT mode only, which means u need a PC and extra steps to finish flashing any ROM.
Some brilliant Dev's managed to use RUU files to update the kernel only, but that also causes issues. If one Dev uses a newer RUU, you can't use the another Dev's older RUU to flash a kernel because the unlocked HTC Bootloader doesn't allow you to "Downgrade" firmware. This leads to headaches with people ignoring the kernel step and screaming because their phone won't boot.
The ultimate Holy grail for is is what is known as "S-OFF"
This allows full access to the HBOOT Recovery and system for all of our awesome devs to work their magic. This was obtained (long after HTCDev unlock) with the Rezound only through a HARDWARE exploit. We needed root exploit (which we had on the GB stock ROM), and to physically short out a pin on the mainboard to ground at precise times while the SOFF program ran on your PC.
We have to wait for the less popular HTCDev unlock (which HTC Did give us on the rezound with a middle finger to verizon), or for some1 to find another Exploit that would bypass the signature check of the HBOOT and give us "S-OFF".
Either will give us Root, custom recoveries, and ROMs.
I am no dev, but this is my understanding of what's happening with these devices. This is my 9th android device, 5th HTC, but I am always learning more. Dev's feel free to correct me, or expand on anything I have written here ^^

[Q] to s-off or not s-off

I unlocked via the htc site, rooted running a gpe rom (not the conversion)
I know that s-off can grant a completely unlocked phone. But i dont really need that. I guess what I'm trying to ask is, what are the advantages? Im not into xposed or gravity box and i dont need my phone carrier unlocked.
will my lack of s-off hinder me from flashing radios and/or newer versions of twrp?
if someone can break this down for me, I would appreciate it
S-off isn't needed to:
- Flash TWRP
- To achieve root
- Flash ROMs
S-off benefits:
- Needed to flash radios (SuperCID also needed to flash a radio that does not match your version)
- Needed to SIM unlock
- Needed to flash modified hboot (such as to remove the red warning text form boot screen)
- Needed to flash firmware components (not the ROM)
- Allows you to run any RUU (other carriers, or even previous RUUs, which is not normally allowed by version check)
The last one is important, since s-off essentially gives you more recovery options if things go south.
But s-off means all security checks are off by definition. This even includes device check, which means flashing a ROM or mod for another device is possible. I've seen folks flash a ROM for a different device with s-off, and brick their phones (due to different partitioning, etc.). As long as you are very careful to only flash things intended for our device, you will be fine. But anyone with s-off (or interested in s-off) needs to understand this.
sheek360 said:
I unlocked via the htc site, rooted running a gpe rom (not the conversion)
I know that s-off can grant a completely unlocked phone. But i dont really need that. I guess what I'm trying to ask is, what are the advantages? Im not into xposed or gravity box and i dont need my phone carrier unlocked.
will my lack of s-off hinder me from flashing radios and/or newer versions of twrp?
if someone can break this down for me, I would appreciate it
Click to expand...
Click to collapse
I'm new to HTC coming from Samsung but I believe for a permanent Uninstall on system apps you need S-OFF. Freezing bloat doesn't always do it for me. Some junk I'd just rather get rid of it.
Sent from my HTC One_M8 using XDA Free mobile app
redpoint73 said:
S-off isn't needed to:
- Flash TWRP
- To achieve root
- Flash ROMs
S-off benefits:
- Needed to flash radios (SuperCID also needed to flash a radio that does not match your version)
- Needed to SIM unlock
- Needed to flash modified hboot (such as to remove the red warning text form boot screen)
- Needed to flash firmware components (not the ROM)
- Allows you to run any RUU (other carriers, or even previous RUUs, which is not normally allowed by version check)
The last one is important, since s-off essentially gives you more recovery options if things go south.
But s-off means all security checks are off by definition. This even includes device check, which means flashing a ROM or mod for another device is possible. I've seen folks flash a ROM for a different device with s-off, and brick their phones (due to different partitioning, etc.). As long as you are very careful to only flash things intended for our device, you will be fine. But anyone with s-off (or interested in s-off) needs to understand this.
Click to expand...
Click to collapse
Thanks for the explanation
Bsmith0731 said:
I'm new to HTC coming from Samsung but I believe for a permanent Uninstall on system apps you need S-OFF. Freezing bloat doesn't always do it for me. Some junk I'd just rather get rid of it.
Sent from my HTC One_M8 using XDA Free mobile app
Click to expand...
Click to collapse
you only need r/w access to completely unistall apps.

[Q] Going to upgrade from an S4 to the M8, and I'd like to know

if HTC allows downgrading the bootloader so I can install a custom rom after I make the mistake of taking an OTA update from ATT. With the S4 this wasn't possible. but since this is my first android phone, I was wondering if it was Samsung trying to keep the device "secure" or ATT forcing these companies to keep their bootloaders locked.
some_douchebag said:
if HTC allows downgrading the bootloader so I can install a custom rom after I make the mistake of taking an OTA update from ATT. With the S4 this wasn't possible. but since this is my first android phone, I was wondering if it was Samsung trying to keep the device "secure" or ATT forcing these companies to keep their bootloaders locked.
Click to expand...
Click to collapse
Once you unlock the boot loader no update can relock it. HTC offers a lot more freedom than samsung, but at the price of no warranty. So if you unlock it and shatter your screen, don't be upset like other people when htc will not warranty it. As long as you have a custom recovery, your phone cannot even physically take an ota update so nothing to worry about either way.
The Magnuson–Moss Warranty Act is in place for us consumers for this reason. The company has to prove that any modification you did, is the cause of the trouble. So if you unlock your bootloader, root, etc, then crack your screen, as the poster above mentioned, the company can not void your warranty since what you did has nothing to do with cracking your screen.
This was huge for me when I modified my car and I found this here on XDA after doing more searching
http://www.xda-developers.com/xda-tv-2/your-warranty-is-not-void-xda-tv/
Oh and yeah,,if you are outside the US, it wont work lol
some_douchebag said:
if HTC allows downgrading the bootloader
Click to expand...
Click to collapse
That depends on what you mean by "allow". You cannot downgrade the bootloader by any "official" means. You will fail version check when you try to install, as you can "normally" only flash a equal or great version number hboot.
But if you are s-off, version check is bypassed, and any hboot version can be flashed.
Similar to a previous response, my advice would be to unlock the bootloader (required if you want to flash custom ROMs anyway) and S-off the phone soon after you get it. Neither of those can be changed by any OTA.
Also, accepting OTA is not recommended on a modded phone, anyway. Whatever came in the update will usually get posted in a stock rooted form in the Development forum, and/or incorporated into custom ROMs, often within days of the OTA rolling out. And OTA will not install on a modded phone (stock recovery needs to be present). OTAs also may plug existing s-off or other exploit; preventing you from doing them if you haven't already (but as mentioned, can't make the phone s-on again). Moral of the story, I strongly recommend against OTA on any modded phone.
Some of these terms/concepts are HTC specific, so may be a bit confusing for you. I would suggest reading up on these forums, if you aren't familiar with s-off, HTC's bootloader unlock process, etc.

Get to unlock bootloader, and then cannot choose to unlock it?

Hello, so I've been trying for a while to unlock my bootloader and at this point I'm quite confused. For whatever reason the power button + volume down combo nation does not load my phone into the bootloader from the off state. Instead it boots my phone regularly. This itself is is not a problem because I can boot it into the bootloader using adb. But inside the bootloader I can move up and down using the list but can't use my power button to select anything. I've also tried booting into recovery and the volume and the power button to choose works fine. I'm just confused at this point and a little frustrated because all I would like to do is install paranoid android, and have not had any problems with past devices. Any help would be appreciated! Thank you.
That is some strange behavior, I agree.
Its been a long while since I unlocked the bootloader, so I don't completely remember what is required. I assume you need to use the vol and/or power buttons to select to unlock; and that is your main problem?
If so, that is a tough one. One thought is to RUU to stock, to eliminate the possibility of some software glitch causing your problem.
Otherwise, plan B is to use sunshine to s-off, than unlock the bootloader. Not sure if that would work, and its an expensive experiment to try ($25). But if it does work, s-off is a nice thing to have. Not expressly needed to flash ROMs, of course. But s-off does allow some other nice tricks, like being able to flash radios, modified hboots, change CID/MID, and removed the requirement to relock the bootloader to RUU.
redpoint73 said:
That is some strange behavior, I agree.
Its been a long while since I unlocked the bootloader, so I don't completely remember what is required. I assume you need to use the vol and/or power buttons to select to unlock; and that is your main problem?
If so, that is a tough one. One thought is to RUU to stock, to eliminate the possibility of some software glitch causing your problem.
Otherwise, plan B is to use sunshine to s-off, than unlock the bootloader. Not sure if that would work, and its an expensive experiment to try ($25). But if it does work, s-off is a nice thing to have. Not expressly needed to flash ROMs, of course. But s-off does allow some other nice tricks, like being able to flash radios, modified hboots, change CID/MID, and removed the requirement to relock the bootloader to RUU.
Click to expand...
Click to collapse
I think I've seen RUU before but for whatever reason I couldn't find it for my phone. Would it make any difference that the phone is AT&T, because from what I've seen people who have the AT&T smartphone tend to run into problems, just not mine.
EDIT: I just took a look at sunshine and am confused, is it an android app that does the s-off? Sorry for what I assume are common knowledge. Looking at sunshine, running 5.1.1 it looks like I need to have to bootloader unlocked to root the phone.
Jkaspar said:
I think I've seen RUU before but for whatever reason I couldn't find it for my phone.
Click to expand...
Click to collapse
All AT&T RUUs are linked on my Index thread: http://forum.xda-developers.com/showthread.php?t=2751432
Be aware that you can only run the RUU version same or higher than what is on the phone (no "downgrading" unless you have s-off).
Jkaspar said:
Would it make any difference that the phone is AT&T, because from what I've seen people who have the AT&T smartphone tend to run into problems, just not mine.
Click to expand...
Click to collapse
There isn't any reason why ATT would be any harder to bootloader unlock than any other version M8, if that is what you mean.
Jkaspar said:
EDIT: I just took a look at sunshine and am confused, is it an android app that does the s-off? Sorry for what I assume are common knowledge. Looking at sunshine, running 5.1.1 it looks like I need to have to bootloader unlocked to root the phone.
Click to expand...
Click to collapse
Yes, sunshine is an app that will s-off the phone, and then also has the option to unlock the bootloader without HTCDev.com (which is fairly trivial once s-off, think it can also by done via adb commands).
Latest Android version for the ATT M8 is 5.0 (.1 or .2, I can't remember exactly).
I'm not sure which versions will work with sunshine without prior root. But you can always install the sunshine app, and it will tell you whether it can s-off or not (and you won't be charged any $ unless it can s-off).
If you do need root before sunshine, some folks have had luck with towelroot (might be temp root, I can't recall). But yes, it complicates what is already just an idea, and not a sure fix by any means.
Sunshine from what I just tried requires root to be installed for the current android I am on. I also just tried using towelroot and it said that my phone was not supported. I am currently in school but I will try the RUU when I get a chance.
Okay so I did the RUU and it worked fine. Booted into the boot loader and nada. Still no luck with the power button. Choosing in recovery still works however. Is there a way to do it purely using adb commands?
You have to unlock with fastboot commands
Like to the screen where it gives me an option to either unlock the bootloader or not? I can get there fine, I just can't choose the yes I want to unlock option.
Jkaspar said:
Like to the screen where it gives me an option to either unlock the bootloader or not? I can get there fine, I just can't choose the yes I want to unlock option.
Click to expand...
Click to collapse
No, that requires button response from the phone
Right which is my main problem

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