HTC One - Crashed during AT&T Software Update, Won't Turn On or Respond

[AC Question]

Hey everyone!

I have an HTC One phone, and this morning it requested that I do an AT&T Software Update. I clicked "Continue", and it said it needed to restart as part of the update. It shut itself down, and I thought it was just restarting but it wouldn't turn back on afterwards. It had charged all night so I know the battery isn't dead, and when I tried to plug it in anyways it wouldn't even light up to show it was connected to the charger.
About a month ago something similar happened - my phone notified me that it needed to install an AT&T Software Update, and after it shut down as part of the restart it wouldn't turn back on. That time I was able to do a Hard Reset by holding down the Volume Down button and Power button at the same time, and it gave me the option to do a factory reset, which I did. It worked well after that...well, until this morning!
I took it to the AT&T Support Center near my house, and the employee said it seemed like the software crashed and there was nothing he could do (for less than $199, at least.) Apparently the warranty is for one year, and since I bought my phone last May they wouldn't do anything (even though it's definitely a phone defect...not due to how I handle it.)

Has anyone else experienced this with their HTC? And is there any way to fix it..?

Thanks in advance!

 

[B. Diddy]

Try booting into Recovery and wipe the cache partition: https://support.t-mobile.com/docs/DOC-6526

If that doesn't work, try talking to someone higher up at AT&T. Ask for supervisors. If their update bricked the phone, it really should be their responsibility to make it right.

 

[Mike Dods]

My ATT phone did the same thing ATT wants me to buy a new phone, this is a known issue and I am working with an ATT rep who is really trying to help me get this situation fixed.