Originally Posted by hollidays24
I rooted my HTC One M8 and I just want to unroot it and go back to sense 6. Please help.
Why do you want to unroot? Its not necessary to do so in order to return to a Sense ROM, if that is why you want to unroot.
If you aren't comfortable with root access for whatever reason, that is a different matter. But root means more access to various functionality, so for those that have bothered to do so, will typically want to remain rooted.
If you want to remain rooted, and just return to Sense, just flash a Sense stock rooted ROM from Development (as mentioned in a previous response). Or one of the awesome Sense based custom ROMs (highly recommended over AT&T's bloated, gimped trash pile of a stock ROM, in my opinion).
If the intent is truly to return to stock, I believe there is a guide in the General section.