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HTC One M8 unusable!

Discussion in 'Android Devices' started by Pierce Gilliland, Feb 3, 2016.

  1. Pierce Gilliland

    Thread Starter

    Okay, so earlier this week the latest marshmallow update popped up and so as usual I began downloading and installing it. I left my phone on charge, pressed update and left it. During install the phone restarted per usual but came to a black screen with a red triangle with exclamation mark (uh oh!).

    I searched online and found how to get to the bootloader. Tried rebooting several times but no luck. I went to recovery, cleared cache, rebooted and nothing happened. Then chose factory reset (I have a backup). still no luck rebooting. Followed many guides on how to fix it using TWRP and placing img files on sd card. Now my phone just powers on to bootloader every time. I can still get into TWRP and fastboot and such.

    I am quite certain that my phone has been completly wiped, drivers an all except the OS is still displayed in the bootloader. I just want my phone to be working again.

    HTC One M8 unlocked, current carrier: giffgaff (O2 network)

    images attached. couldn't rotate them.

    Please help ASAP


    Attached Files:

  2. Best Answer:
    Post #12 by saltire, Feb 4, 2016 (1 points)

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  3. saltire

    saltire Android Expert

    Did you try and take the OTA with TWRP installed and unlocked bootloader, or have you flashed this after to try and fix?

    Trying to determine if you have a TWRP backup you can restore or not?

    What guides have you tried to follow, links would be good?

    If you have a TWRP backup easiest fix is to restore it.

    It looks like some or maybe all the firmware installed ok from what the OS line in bootloader is reporting. But we don't know how much unfortunately.

    Plus I need to check if there is a stock MM TWRP backup available from a reputable source.

    How far did you get in following the guide you mentioned, in order to fix this using TWRP? Did you find and adownload a wwe 6.12.401.x backup?

    Edit: if a mod stops by this is probably better moves to the M8 sub-forum.
    Pierce Gilliland likes this.
  4. Pierce Gilliland

    Thread Starter

    Thanks for replying.

    I'll be honest and say that I tried several things and I cannot quite remember exactly what I did as most attempts seemed to do nothing.

    Not sure what OTA is.

    I did not create a backup on TWRP until much later (after all attempts) and so i assume it is useless. (after wiping)

    I tried flashing, installing stock drivers and such. nothing worked.

    I cant remember all the guides but here are some links I bookmarked throughout:
    (I didn't really know what i was looking for)






    p.s. I created a thread with the same post on sunday the person replying said they would move it to the M8 sub forum. They never did and wouldn't reply again so i created this thread today.
  5. saltire

    saltire Android Expert

    OTA is just the over the air update.

    Ok, I'm out tonight but will pick this up tomorrow. In the meantime don't panic and don't be tempted to try anything else for the moment. We want your bootloader working just as it is.

    I know you want it fixed, but try and be patient.

    One of the other guys might chime in to help as well.
    Pierce Gilliland likes this.
  6. Pierce Gilliland

    Thread Starter

    OK thanks very much.

    I don't see how i could try OTA with TWRP as the phone could not launch the OS.

    I installed TWRP to then use img files, flashing, etc. which strangely enough stopped the black screen with red error triangle/exclamation mark after start-up screen(white screen/green HTC logo). now phone just goes to bootloader on start-up.

    I hope this helps/explains some of the situation. I really don't understand anything about smartphone troubleshooting.
  7. saltire

    saltire Android Expert

    One other thing, do you have a Win PC and adb/fastboot tools on it? There's a thread on the site with a mini-sdk and install guide on the site (sorry can't remember where). It would be useful to get this set up as we'll probably need it.
    Pierce Gilliland likes this.
  8. Pierce Gilliland

    Thread Starter

    yeh windows PC and now you mention it, yes i downloaded adb and fastboot tools from a guide i followed. also managed to find the link:

    From what i remember i couldnt continue on with it because it required connecting to PC. My PC cant recognise my phone though. It could before as i would use HTC sync manager for moving music and stuff but i would have to leave the phone open on home screen for it to connect. I think it's usb debugging or something. Anyway i cant change that option on the phone in its current state.
  9. saltire

    saltire Android Expert

    Quick test. Don't worry about ish debugging, doesn't affect fastboot. Can you switch bootloader to fastboot (from your first pic, use vol down key to highlight fastboot in the menu, and power to select) and connect to pc, and check screen to make sure it shows:

    fastboot usb
  10. Pierce Gilliland

    Thread Starter

    yeh i can switch to fast boot but doesnt connect to pc.
  11. saltire

    saltire Android Expert

    Just to clarify, make sure you exit HTC Sync fully. With the phone in fastboot when you connect to PC, on the phone screen do you see "fastboot usb" or not?

    With HTC Sync installed you should have correct drivers, so PC should recognise the phone in fastboot mode.
    Pierce Gilliland likes this.
  12. Pierce Gilliland

    Thread Starter

    Ah i see, yes it switches to fastboot usb.
    saltire likes this.
  13. saltire

    saltire Android Expert

    Perfect. Right have found what we need in terms of a stock 6.12.401.4 TWRP backup. Two things we need to know or sort out first. Ideally we need to confirm your CID number (although I reckon this will be HTC__001 from your bootloader info and carrier), and we also need to know your phone's serial number.

    Reboot phone to bootloader and plug in to PC (so you see FASTBOOT USB on bootloader screen). Open a command prompt window in the adb/fastboot folder on your PC - if in Explorer hold shift + right click, and pick "Open command window here" from context menu.

    Then type:

    fastboot devices (to check fastboot connects to phone ok, it should also return the phone serial number - write this down carefully as we will need it later)

    If it does, then type:

    fastboot getvar all (this is just a check - confirm from the list that's returned what the CID number is eg HTC__001 , you can also double check the serial number as well )

    If the CID for some reason is different just make sure it is one of the numbers listed just above the two 6.12.401.4 download links in the first link to the xda post in step 1) below.

    Edit: as a further check on the firmware you have, make sure that in the info returned from the "fastboot getvar all" command, under Version-main this matches the firmware number 6.12.401.4

    Next steps to get you up and running:

    1) On PC download the TWRP backup files you need from here:


    pick one of the two download links for 6.12.401.4

    Plus the stock recovery, which is handy to have if you want to fully return to stock, from here:


    again, you want the 6.12.401.4 download link

    2) Next, do you have a micro sd card in the phone? So you can copy the TWRP backup files you downloaded to the micro sd card and access them in TWRP. The main point to note is that you need to place the extracted files from the zip or rar file in a folder, on micro sd card, with the following name:

    TWRP\BACKUPS\<your phone serial number>\<backup folder name>

    The phone's serial number is what you noted down - the <your phone serial number> folder you create needs to match this exactly.

    For <backup folder name> give it a name you'll recognise eg Stock_Backup - this can be can be whatever you like, I tend to avoid using spaces just in case.

    The key point is to make sure you have placed the extracted backup files in the above folder, so once we get the later version of TWRP flashed (see below), it will pick up the files for the restore. When you extract the zip/.rar file I suspect you'll find a folder extracted with a name that ends in "... release-keys" it is the files in this folder that you need. You can just use this folder if you like, but as this will appear in TWRP as the backup name I think something called "Stock_Backup" is easier to recognise and deal with.

    If you do this before the next steps, it'll save a bit of time.

    3) Then download the latest version of TWRP recovery from here, and save to folder on PC where you have the fastboot.exe:


    I'd go for at least the version but latest version should be fine. Check the md5sum for your downloaded file matches - the md5sum link is at the top of the website download page, and the mini sdk zip file includes a md5sum checker in it if you haven't got one.

    If md5 checks out, reboot phone to bootloader and plug in to PC (so you see FASTBOOT USB on bootloader screen). Open a command prompt window in the adb/fastboot folder on your PC - if in Explorer hold shift + right click, and pick "Open command window here" from context menu.

    Then type:

    fastboot devices (to check fastboot connects to phone ok, it should return the phone serial number)

    If it does, then type:

    fastboot flash recovery twrp- (assuming you downloaded the latest TWRP)

    4) Then we need to check you can get in to TWRP ok, on phone bootloader screen use vol down to highlight HBOOT from the menu and press power button to select. Wait until HBOOT finishes check (some green text appearing on screen), then select RECOVERY from menu using vol down and pressing power to select.

    This should load TWRP. Then you want to do the restore of the backup you downloaded, so select Restore to get into the restore screen. Now you need to point TWRP to your external SD card, look for the line of text in restore screen that will say something like Internal Storage, press on it and then select External SD Card (or might be Micro sd card, can't recall off the top of my head) - it should be obvious which to select. You should then see the backup listed.

    Press on backup name, you should then see a screen with various partitions to restore selected (ticked), there should at least be Boot, System and Data. Then at the bottom swipe the slider left to right to start the restore.

    At this point, once restore has completed successfully, I would reboot phone and check it boots ok and complete initial set-up before moving on to the stock recovery step. If it boots ok, you might have to reboot back in to TWRP and do a data only wipe if there are any artifacts hanging around from the backup you have just restored. Let me know if that's the case.

    [Optional if you don't want to keep TWRP, and get back to stock - I wouldn't until we're sure phone is working ok]
    5) On PC, copy the stock recovery image you downloaded to your fastboot folder, reboot phone to bootloader and plug in to PC (so you see FASTBOOT USB on bootloader screen). Open a command prompt window in the adb/fastboot folder on your PC - if in Explorer hold shift + right click, and pick "Open command window here" from context menu.

    Then type:

    fastboot devices (again just to check fastboot connects to phone ok, it should return phone serial number)

    If it does, then type:

    fastboot flash recovery recovery_6.12.401.4.img (I haven't downloaded this so the "recovery_6.12.401.4.img" filename might be different, just type this with the correct filename if it is)

    This should be you back to 100% stock rom/kernel and recovery i.e. unrooted.

    [Optional if you want to go fully back to stock]
    6) Then if you want to, the last part is just a case of relocking the bootloader and the phone should be set for OTA updates. At this stage until we are sure everything is ok I wouldn't recommend doing this, in case we need to get TWRP back on. Command for this from PC is:

    fastboot oem lock

    Let us know how you get on.
    #12 saltire, Feb 4, 2016
    Last edited: Feb 5, 2016
    tafamus, dan55, Granite1 and 3 others like this.
  14. Pierce Gilliland

    Thread Starter

    Woah haha ok. I'll have to look at this tomorrow though as I am busy at the moment and will be travelling later today.
  15. saltire

    saltire Android Expert

    No probs it'll be here.

    @El Presidente only 'cos I saw you dropped by this is probably better off in the Root M8 sub-forum, thanks
  16. El Presidente

    El Presidente Beware The Milky Pirate!
    VIP Member

    Moved to the M8 root area. :)
  17. Pierce Gilliland

    Thread Starter

    Sorry for the delayed reply, weekend has been very busy.

    phone serial number: -

    CID number: 11111111

    The CID number is literally eight ones for some reason. I assume it should be HTC__001 or similar when looking at the download links. Any idea?
    #16 Pierce Gilliland, Feb 8, 2016
    Last edited: Feb 9, 2016
  18. saltire

    saltire Android Expert

    Ok you have super CID set. Interesting since your phone is s-on, which is unusual as changing the CID requires s-off, and having gone to the bother of gaining s-off on the phone I don't know why this would be reverted back again.

    Edit: Also scrub your serial number out from above post just in case, as long as you have a note of the exact number no-one else needs to see it.

    Other than that, you should be good to go.
    #17 saltire, Feb 9, 2016
    Last edited: Feb 9, 2016
    Pierce Gilliland likes this.
  19. Pierce Gilliland

    Thread Starter

    Ok i have completed all the steps, all seemed to work. However i have not entered 'fastboot oem lock' in command prompt which is at the end of the guide above. Should i go ahead and enter this?
  20. saltire

    saltire Android Expert

    Tbh I wouldn't complete the last step just now. If another OTA appears then you can do it before accepting it. But if you just want to return fully to stock, and are happy phone is 100% then go ahead.

    Is your internal storage still intact? I would recommend you take a full copy of what's on it to your PC as soon as.
    Pierce Gilliland likes this.
  21. Pierce Gilliland

    Thread Starter

    How do i launch the OS on my phone. I still cant do that.

    When you say internal storage do you mean my apps, music, videos, images, etc?
  22. saltire

    saltire Android Expert

    So didn't you reboot after completing step 4 to make sure phone boots successfully? If you are still in fastboot on phone in command window type:

    fastboot reboot
    Pierce Gilliland likes this.
  23. Pierce Gilliland

    Thread Starter

    ok, it reboots back to fastboot usb
  24. Pierce Gilliland

    Thread Starter

    also i notice i cannot get back into TWRP. when i select recovery in hboot an error screen comes up instead.
  25. saltire

    saltire Android Expert

    Hmm, yeah you won't get back to TWRP if you completed step 5 anyway, it would be stock recovery. Can you try:

    fastboot erase cache

    And then try rebooting.

    If that doesn't work then it sounds like the firmware install may have got borked somehow.

    There's another thing we can try but am travelling now so will need to wait until tomorrow.
    dan55 and Pierce Gilliland like this.
  26. Pierce Gilliland

    Thread Starter

HTC One M8 Forum

The HTC One M8 release date was March 2014. Features and Specs include a 5.0" inch screen, 4MP camera, 2GB RAM, Snapdragon 801 processor, and 2600mAh battery.

March 2014
Release Date

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