Make sure to select a restore date prior to when the problem started.
Also, see if this helps:
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ARE YOU HAVING DIFFICULTY WITH GETTING "EXE" FILES TO ACTIVATE?
Click Start - Run, type in REGEDIT, then click OK.
Click the + in HKEY_LOCAL_MACHINE - Software - Classes - Exefile - Shell - Open.
Click directly on the Command folder to expose its entries in the right pane. Make sure that Default is set to "%1" %*
If it has a different value, right-click it, then click Modify.
Change the value to "%1" %*(quote, percent, number one, quote, single space, percent, asterisk), then click OK.
Close the registry, then reboot your computer.
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