HTC One M8 system upgrade failure, what should I do?

[AC Question]

HTC One M8 system upgrade failure

System upgrade(1/30/16) failed at 86%. Now every action returns phone to the reboot screen. However, rebooting the phone returns the phone to the reboot screen! What should I do? Thank you.

 

[B. Diddy]

Re: HTC One M8 system upgrade failure

Welcome to Android Central! Are you able to boot into Recovery and wipe the cache partition? https://support.t-mobile.com/docs/DOC-10672