LogFAQs > #895969453

You have four options that are viable: copy your steam\steamapps\common\ to keep your games to another folder, uninstall steam and then reinstall it, copy over those game folders and hope it works fine, shut your PC down and hope when you boot it up that it works fine now, you can restore to an earlier state in your laptop (assuming you have one) or else reinstall Windows.

I'd recommend doing them in order to see if they work.