[HTC Desire Eye] NinYagami:
Here's the situation I'm in right now.

My phone is the HTC Desire Eye AT&T Model. I am not rooted, S-Off, Relocked, and on Stock Recovery and Lollipop Rom.

When in Fastboot mode the top of the screen reads:

*** Software status: Modified ***

*** RELOCKED ***

EYE_UL_CA PVT SHIP S-OFF

CID-11111111

HBOOT-3.19.0.000

RADIO-4.0.U605641@50528.2A

OpenDSP-v47.2.2-000564-M8974.1024

OS-2.09.502.3

eMMC-boot 2048MB

Aug 18 2015,20:36:07.0

Some information on how I got in this predicament:

My home internet provider is absolutely cancerous, such that tethering my 4G LTE connection is much faster.

I had an unlocked, S-Off, TWRP installed phone.

I am using T-Mobile right now, and I needed a way to tether my phone, which the phone does not allow through T-Mobile.

I did a Nandroid backup of my phone using TWRP

So, I unlocked the bootloader and installed the Taiwanese Lollipop ROM, then rooted from TWRP. I was now able to tether, and that was good enough for me.

Later, I found that Marshmallow was released. I wanted to receive the Taiwanese OTA update (AT&T could not give me the update, similarly to tethering, on T-Mobile).

I changed the CID to SuperCID. Somehow, I believe using some hex editor method, I changed the MID. However, the update could not be flashed because the Product ID was "eye_ul", which I still could not find out how to change. Even modifying build.prop didn't do anything.

I decided I must have went wrong somewhere, so I decided to start back at square one. This is where things went wrong. After I flashed the original backup I made of my phone, it was no longer rooted. I then proceeded to lock the bootloader, so I not only lost my custom recovery, but the way to flash it back as well. I went back to HTCdev and performed the unlock process, but there was this error described here.

I am aware that EYE_UL_CA is the AT&T product name, CID 11111111 is SuperCID, these two are fine.

However, the Model ID 0PFH20000 is Taiwanese. The original AT&T MID is 0PFH10000, but I don't know how to change it back

When running the command fastboot getvar all here is the information:

[IMG="fastboot getvar all"]https://i.gyazo.com/89b408cf70889245a0ac5d9968c4888e.png[/IMG]

The unlock token I received was:

<<<< Identifier Token Start >>>>

41235A6270C9338D6B0CDC8783A0B2C8

D647EB5E2F2A2FE7828A885DB6214D97

41E99F77EA8619250FD1367851924861

A46DCD4301228035FD62578DFDC6A843

F79115EC1EBDCFB8AA95BA73F62C0E2A

30F58D5AA67DDA97F91F625099943710

D708BC3BB462F7AD71A70BDC06234766

4E7DE5F4116B1BB2B6FA46C52A72645B

A6416C72CA39E41CAF8031231E3A44CF

D304616C3BD5955DA409654FAF91880B

187F7079B8CBC57EE45714B94B4823AD

265BDFC7D61B32F8357C658DAC24977D

FCD99AB305B23943E2E6678D4B8C3331

5A7A4D997CABD525F6D2BAB1DF241936

C78DF80041A4690031D448A2C462FE9C

7433BF2B54ACC53C10AA8B6F2E71EE48

<<<<< Identifier Token End >>>>>

Then unlock_code.bin file is attached as a txt. When I try to flash it with fastboot flash unlocktoken unlock_code.bin, I get the following error message. FAILED (remote: unlock token check failed).

[IMG="unlock token error"]https://i.gyazo.com/62c11be54c9334a848f1fb9f79b9d2ca.png[/IMG]

I read that running the original RUU makes unlocking work again. However, I cannot use it because the device Model ID is still Taiwanese, and I am unsure of how to change it back to the AT&T version.

It's possible that all these problems are because I cannot remember how to change my MID back. fastboot oem writemid is not a command that works on my phone ((bootloader) [ERR] Command error !!!). I remember working with a hex editor to edit some file, but I forgot what it was.

I know it's possible to change the MID back to AT&T because it's impossible to have started out as a Taiwanese MID.

Right now, I can't use my phone to tether, so I am using my incredibly slow home internet to post this. Please Help Me!

Update: I now have root access, and I have reverted the MID back to 0PFH10000. I installed the RUU, but the bootloader still has the same error when I try to unlock it. Please let me know if you are an expert in this error and know how I can unlock my relocked bootloader. Thanks!