Looks like an AT&T model to me. Something that is not clear to me: Did you convert your phone to GPE or not? The partiton sizes are different so, if you did a GPE conversion you would need to convert your firmware partitions back.
If you didn't convert to GPE, you should just be able to restore a CWS__001 backup from the stock backups thread in the general section, flash stock recovery and download/install the OTA.
Yes, I have an AT&T HTC One M8. As far as I know, I never converted to GPE. Here's a history of what I've done as far as flashing goes.
Unlocked bootload, rooted, went S-Off, flashed Android Revolution, flashed Viper ROM, went back to Android Revolution then tried to go back to stock and broke my phone. Now I'm back on Android Revolution. I did a whole bunch of factory resets/dalvik wipes and such so maybe that's why it looks confusing?
You are going to have to flash your current firmware first before installing it for the OS info to show up again in HBOOT. You can use the Flashify app to install it or else just do it the PC/ADB way using command prompt like I did. It totally worked for me, so go ahead and try it!!
If you have questions on how to flash anything, lemme know.
Hey........ disregard my previous message. That version of TWRP DOES work (fixing "Blank OS" issue), HOWEVER........ I created a new backup using it and then tried to restore it over the weekend........... IT DIDN'T WORK! I think something is corrupted with it. So anyone who clicked on that link and got that version of twrp, delete it and ANY BACKUPS YOU CREATED WITH IT immediately. They are corrupted and useless.
Fortunately though, I was able to find a fully-operational version of TWRP over the weekend that has no issues and it too fixes the "Blank OS" problem too. Here you go:
Don't worry about it saying Sprint...... the dev CONFIRMED it works for all variants/carriers. So after creating a new backup using the standard twrp, I went back to stock recovery, re-flashed my most recent firmware (2.22.401.5), and then switched over to that new version of twrp........ created a new backup and then restored it using that new version. Worked like a charm!! And the "blank OS" issue........... gone! I highly recommend it!!
So please delete that old twrp and any backups you created using it, and you should be good to go!
P.S. My thanks to Midasgalp and also Captain Throwback!!
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