[One (M7) Q&A, Help & Troubleshooting] nkk71:
First off: the below procedure is going to wipe everything off your phone, so backup anything you need to your PC!!

Step 1: go back to Sense 5 Stock

fastboot oem writecid HTC__001 (two underscores)

fastboot reboot-bootloader

-> and confirm CID is HTC__001

Run the following RUU, to downgrade to stock Sense 5: http://www.htc1guru.com/dld/ruu_m7_...1-27_10-31-1131-05_release_310878_signed-exe/

This will completely return you to 100% stock Sense 5, but European unbranded version.

Step 2: go back to H3G__001

fastboot oem writecid H3G__001

fastboot reboot-bootloader

-> and confirm CID is back to H3G__001

Step 3: restore H3G nandroid

download CWM from here: http://xdaforums.com/showthread.php?t=2173863

fastboot boot recovery-clockwork-touch-6.0.4.5-m7ul.img

you should now be in CWM recovery.

download this nandroid: http://www.htc1guru.com/dld/m7-cwm-nandroid-backup-cid-h3g__001-1-28-771-x-2013-04-09-zip/

extract the zip on your PC, it will give you a folder called "2013-04-20.21.00.00" place it in your adb folder then push it:

adb push 2013-04-20.21.00.00 /data/media/clockworkmod/backup/2013-04-20.21.00.00

in recovery select RESTORE, it should show you the above backup, so select "2013-04-20.21.00.00" and restore it.

You still need to get the preloaded stock apps (which get deleted when unlocking using HTCdec), so download this:

http://loadbalancing.modaco.com/download.php?file=one-1.28.401.7-preloaded-modaco-withoutmovie.zip

adb push one-1.28.401.7-preloaded-modaco-withoutmovie.zip /data/media/

in recovery, select "install zip" -> "choose zip" -> and install the above file

Step 4: get back stock recovery

the above nandroid may or may not contain stock recovery, but I doubt it does, so get this: http://d-h.st/uGM

now let's reboot to bootloader/FASTBOOT USB:

adb reboot bootloader

fastboot erase cache

fastboot flash recovery recovery 1.28.401.7.img (closest one to your version)

fastboot erase cache

Step 5: let's get rid of TAMPERED (if it's there) and set you back to LOCKED (not relocked)

fastboot boot recovery-clockwork-touch-6.0.4.5-m7ul.img

download this: http://www.htc1guru.com/dld/guru_bootloader_reset_1-0-zip/

adb push Guru_Bootloader_Reset_1.0 /data/media/

in recovery, "install zip" -> "choose zip" -> and select "Guru_Bootloader_Reset_1.0"

go through the installer and select "Remove TAMPERED" and "LOCK Bootloader"; once finished, and since you're still in CWM, go ahead and:

-> "wipe cache"

-> "advanced" -> "wipe dalvik"

then

adb reboot bootloader

and confirm no TAMPERED and LOCKED status

Step 6: get your 1st OTA

finally (almost) to confirm everything is back to 100% stock, reboot your phone, and set up only basic stuff such as WiFi, check for software update and download & install the

1st one only

!

Since recovery is not exactly your version, you may need to reboot your phone manually if it doesnt by itself: the progress bar stopped somewhere in the middle -> press and hold POWER + VOLDOWN, when it reboots keep holding VOLDOWN to get back to stock recovery and let it finish it's business; repeat if it gets stuck again

After finishing the OTA, boot up your ROM, and check you

Settings->About

to confirm you new version, then reboot to bootloader and do a fastboot getvar all, and confirm firmware and hboot are also updated

Step 7: if YOU decide to go S-On

fastboot oem writesecureflag 3

reboot 3 times and make sure it doesnt say "tamper detected - rebooting" and then shows TAMPERED again

as far as I know, this was introduced in hboot 1.55

I really think I should start a universal guide, hmmm

EDIT: I'm sleepy so I hope I didnt forget anything!!

EDIT2: I'll post credits to all those links when I get a chance, sorry guys

Hit the thanks button if I've helped ;)