HTC One Mini, unable to unroot

[ricc0m]

HI all,
i rooted my phone and after using CM11 for a while i can no longer cope with the regular battery drains and it just shutting down for no reason.

I have tried & tried to get s-off, run RUU and flash other ROMs but I get an error message in TWRP recovery 'checking for md5.....skipping md5 check no file found'

Please can someone help as the phone is near enough useless as it is......