Today my trusty HTC One M8 informed me that OTA (over the air) update of system software is available. Android security updates. Naturally I let the system download and install the update. Unfortunately after install phone refused to boot – it was getting stuck on HTC logo on white screen. Bummer.
Now I researched “stuck on logo” topic in depth and tried different methods to unstick it. No dice. Moreover, after chat with HTC Support and following their advice phone would simple go to blank screen. Double bummer.
I decided I have nothing to lose and go for custom ROM. Besides, custom ROM often offers numerous advantages. After digging around a bit I decided to go with Sky Dragon ROM downloaded it and saved on harddrive for now. Next thing I needed was custom recovery – and TWRP is the best choice there. Downloaded that as well and saved locally.
To install custom recovery you need to place your phone into Fastboot mode. To do so power your phone down if you can, then press Power + Vol Down together and after phone starts release Power but keep Volume Down pressed. If you cant’t power the phone down – press and hold Power + Volume Up together. When the phone begins restarting – release Power and Volume Up and press and hold Volume Down. Note that if your phone is originally stuck on black screen and not HTC logo you will need to time this precisely since there will be no visual clues. Press and hold Power + Volume Up for 11 seconds and then immediately release them and press Volume Down.
The phone will enter menu. Using Vol Up/ Vol Down buttons select Fastboot option and press Power button. Phone enters Fastboot mode. Connect phone via USB to your computer (note: you need correct drivers installed, see TWRP page for details) Using ADB Tools mentioned on TWRP download page issue this command: fastboot flash recovery twrp.img where “twrp.img” is the name of recovery file you downloaded. After recovery gets copied, issue command fastboot reboot – phone will reboot into initial menu. Now select “Recovery” from the options. Phone will boot into TWRP Recovery and appears as a connected device on your computer. Copy ZIP with the ROM file you downloaded onto the phone (remember location). From TWRP options select “Install”, point to the ZIP file you copied and swipe slider to flash it. Install will take it from there.
After ROM is installed, reboot the phone and finish the install.
UPDATE 10/29/2015: After running SkyDragon for a few days I found out that it drains battery really fast. So I switched to Stock ROM GP Edition.