Used MBAM to remove SlimCleaner Plus - removed quarantined files, now most normal PC files gone.

I was helping my grandparents to remove SlimCleaner Plus from their PC as it was badgering them with pop-ups. I installed MBAM and did a scan, with around __ files related to SlimCleaner appeaing as PUP's. I quarantined and removed these files, and restarted the PC per MBAM's requests. After restarting, many files were deleted. There are also some invisible notifications appearing, and some strange crashes occuring so I believe some system files were deleted as well. Is there any way to...

Used MBAM to remove SlimCleaner Plus - removed quarantined files, now most normal PC files gone.