I bought an HTC ONE M-7 from a user who was running it on a custom Rom and had it S-OFF.
While trying to put stock Rom on the phone via the pc, the pc crashed in the middle of the process and the mobile stopped responding. The phone stayed in this condition until the battery ran dry. Since that moment, the phone doesn't turn on by any combination of hardware buttons as mentioned on different forums. While plugged in to a power source the screen just blinks on and off.
I would be highly obliged if anyone can help me out of this situation.