I can’t begin to tell you how many people have had problems here at work with Adobe Reader version 10.1 and up! Their software keeps getting crappier and crappier. Ditto to msconfig, safe mode and if necessary, recovery/repair. Going forward, ditch adobe reader and try Foxit PDF reader instead!
I second Foxit Reader for PDFs... nothing can match it.. (VERY low resource use, and almost instant view).