how do l fix s-on on my htc one m7

[akinyele]

My htc one m7 s-on changed to s-off, incidentally also the OS was mistaking ly wiped. Attempting to install or retrieve it has proved abortive. Series of os is to be install but failed to mount. Kindly advise on how to fix this problem to get the phone to its stock state

 

[dpham00]

Mod Note, I will move this to the m7 forum for more visibility