[One (M7) Q&A, Help & Troubleshooting] Danny201281:
A friend has asked me to try and fix there M7 ul. It was. Completely stock on O2 UK. They got a notification for system update (4.4.2 Sense6.0). While installing they left the phone and when they came back it was off. After some fiddling they managed to get it to come on but it would only boot to the bootloader which had Tampered and Locked flags.

This is where I came in so I tried booting to stock recovery to see if the OTA would complete but it was a no go. The screen just stayed black for ages then eventually would show the phone picture with red exclamation. Using volume up+power to get the recovery menu to reset cache returned it to the normal picture with green arrows. But reboot and repeat :( So I tried fastboot erase cache and attempted ota again with same results.

At this point I told them that anything more I tried may void the warranty so better to send it in but there is no warranty so asked me to do whatever I can. Naturally for me the next step was to unlock the bootloader to regain some control. First I just let the phone boot this time no bootloader screen but it just looped on the HTC splash screen.(i kind of expected that). So next I reboot bootloader and flash twrp2.6.3.3 erase cache and boot recovery. ARHD rom was already in my android folder so pushed it strait over. Ran into some pitfalls trying to flash the rom like instant reboots when flashing started and disappearing zip files fixed with e2fsck, zip failed message fixed with Format data and eventually got the rom installed. I know first boot normally takes a while but this seemed longer than expected but eventually booted the rom and everything seemed to be working fine.

After setting up the basics and testing a few things (installing and running apps. Playing music and so on) I rebooted the phone but again it bootloops on HTC splash screen. Tried everything to get it to boot like wipeing cache/dalvik, dirty flash, clean install even fix permissions nothing worked except Format Data in Twrp Full wipe, re-push rom re-flash rom. Phone took a while but booted and again worked perfectly while setting up and using the phone. So tried restart and again bootloop on HTC splash :(

So I'm now at a point where I think I've narrowed it down to the Kernel or Ramdisk or atleast the partition there installed on. Since if I use the Superwipe script to wipe only the boot partition cache/dalvik then refresh the boot.img or flash a kernel from recovery (i've been using bulletproof kernel) the phone will boot with the rom and settings intact.

If there is a problem with this partition I do not know how to fix it. I know mmcblk0p33 is the boot partition but is it where the boot.img actually lives or is that the bootloader partition?

If it is the boot.img partition can I repair it with mke2fs or e2fsck or some other tool?

There is an ruu available for the device so if I can just stop the bootloop I could s-off and then ruu and return it to stock. But firewater won't work and I think it's because of the procedure involved in getting the phone to boot is interfering with the push somehow. Firewater will push ok and chmod works but when I try to run firewater nothing happens and then the firewater file disappears and I have to push it again which means re-wipeing and flashing the kernel. I'm really not sure where to go from here any help or suggestions would be most appreciated thanks in advance :fingers-crossed: