[One (M7) Q&A, Help & Troubleshooting] sartorius73:
Stuck on 4.4 with locked bootloader

This looks like the place for noobie questions. I recently moved from an iPhone to a Google Play Edition HTC One, which is much better. I've installed Tasker, but want root access to take advantage of more of Tasker's capabilities. Perhaps I'll try some custom ROMs later. I've installed ROMs on Playstation Portables, and my iPhone was always jailbroken. So, I'm somewhat familiar with ROMs and such things, but not very knowledgeable about Android-specific hacking.

Anyway, I recently updated to 4.4 Kitkat, and I hate it. Google Voice integration doesn't work as well, and I like the blue/gray network bars. In looking around, it looks like I can flash back to 4.3 or a custom ROM. However, I've never unlocked the bootloader. It never occurred to me until I needed to get root for tasker. My brother has the same GPE phone and unlocked his bootloader on 4.3 using the "fastboot oem unlock" command. He's running Cyanogen.

I have tried, without success, to unlock the bootloader. I have the SDK and HTC One driver. I have USB debugging enabled, and I can boot into fastboot mode.

When I'm booted into fastboot USB, I can run "fastboot devices" in the Windows 7 cmd window and I get my HTC device listed, so I know Windows is seeing it. I can also see "My HTC" in the device manager.

My fastboot screen says:

***LOCKED***

M7_UL PVT SHIP S-ON RH

HBOOT-1.54.0000

RADIO-4T.21.3218.21

OpenDSP-v32.120.274.0909

OS-3.58.1700.5

eMMC-boot 2048MB

Nov 21 2013, 20:19:24.0

When I do the "fastboot oem unlock" command, I get this error:

(bootloader) [PG_ERROR] htc_pg_part_traverse(839):

(bootloader) invalid traverse range

(bootloader) [PG_ERROR] htc_pg_part_read(1029):

(bootloader) htc_pg_part_traverse failed

(bootloader) [DISPLAY_ERR] sp_custom partition: unlock_disp_buf.img_buf r

(bootloader) ead error!

(bootloader) [DISPLAY_ERR] Can not load custom splash!

(bootloader) Loading custom splash failed!

OKAY [ 0.554s]

finished. total time: 0.556s.

The phone doesn't freeze, it doesn't take me to the splash screen to select bootloader unlock. Nothing happens.

I've tried the htcdev.com bootloader method. I can successfully generate an identifier token, and HTCdev will email me the Unlock_code.bin file. When I run the "fastboot flash unlocktoken Unlock_code.bin" command, I get this response:

target reported max download size of 1526722560 bytes

sending 'unlocktoken' (0 KB)...

OKAY [ 0.143s]

writing 'unlocktoken'...

(bootloader) unlock token check successfully

OKAY [ 0.006s]

finished. total time: 0.154s

But, nothing happens on the phone. The phone is still connected, because I can generate another identifier token and get a response to "fastboot devices".

In reading many, many posts and forums, it seems that this bootloader unlocking has been problematic in 4.4. I read lots of posts about running RUU, flashing to an older Hboot version, installing recovery ROMs like TWRP and CWM, switching to S-Off with Moonshine or Rumrunner.

But, every option requires an unlocked bootloader. So, how do I unlock the stupid thing? I'm hoping there's some simple answer I'm overlooking. But I can't find it.

Any suggestions would be greatly appreciated. Thanks in advance.