Having the same problem. Flashed the latest cyanogen nightly last night and that seemed to go normally. Then flashed GApps. Also appeared normal. Then got a screen saying I wasn't rooted and asked me if I wanted to flash Superuser. Yes. Then nothing. After waiting about 30 minutes I pushed power/vol up and got a normal htc splash then black.
Have tried to access from adb and fastboot to erase cache and just get "waiting for device". Have tried power/vol up then as soon as the splash appears and/or disappears then sliding my finger to vol down while still holding power and still nothing.
Phone was quite warm (not quite hot) when I went to bed last night and this morning battery was at "0". When I first plugged it in and pushed the power button it alternated from the battery charging display to the TWRP locked screen but I couldn't seem to get it to stay on the TWRP screen no matter what I did. Now that I've used power/vol up I don't seem to get the battery or TWRP. just black or when trying power/vol up I get the splash. Power/vol down gives nothing - just black.
Hope it's not completely bricked. Really need help this time. Thanks
EDIT: Just tried - let battery go dead. Plug in to computer hold power/vol down. Screen goes from battery icon to blank and back to battery icon.
EDIT: Pulled and reformatted sd card in Evo 4g LTE. Retried fastboot command still just shows "waiting for device". Even tried adb reboot bootloader and reply "device not found"
Could I use adb to reflash ruu? If so would the command be adb flash (filename)
Was beginning to loose hope of ever fixing this but a HUGE shout out to Simer03 who provided the critical piece of information - namely - add a ROM zip to your sd card. Hope nobody else ever has this problem but just in case
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