I have a Toshiba Satellite P875-S7102 Laptop that began operating very peculiar because the Windows 8.1 operating system s-l-o-w-e-d down. Click an Icon to initiate a web browser (or anything else) and go make a pot of coffee while you wait for for the icon to acknowledge you even clicked it, much less start IE. After a few restarts the system would show this after unit startup: "Repairing disk errors. This might take over an hour to complete." I left the system alone overnight twice and the farthest the "repair" ever got was 1%. I suspect that the hard drive may have a physical dilemma, but not sure. The first time the laptop did this (3 days ago) it decided to completely reinstall Windows 8.1 without any input from me. Three days later with remarkably slow and dysfunctional Windows (again) it is now "Repairing disk errors. . ." again. What do you folks think? Thanks in advance.