digital storage of media. The recommendation from below link is to disable it from starting at boot-up which could by pass your problem.
http://www.bleepingcomputer.com/startups/DMAScheduler-16876.html

If has been damaged some how (say by spyware removal tools) it may be repairable by re-installing the HP software containing it.

Possibly it's function is being blocked by say your A/V Security program
like Norton etc. as Norton / McAfee/ etc. may run it's own archive and possibly same may affect system restore if it runs a back up/restore function built into it & disables SR in favor of it's own functions.

I would wonder, IF above not the case, whether SR has been disable by a current or past infection, which might be corrected by running a SFC scan to repair SR files (as long as infection is NOW gone).

Much more info on protectors & time line would likely be needed to pin-point this further. Happy