Thank you very much, your short, quick tutorial was successful and got all my .exe's running again!Use this tutorial :
Default File Associations - Restore in Windows 8
http://www.eightforums.com/tutorials/8486-default-file-associations-restore-windows-8-a.html
1.Scroll down to the table and select .....
.exe
2.Save the .reg file to your desktop.
3.Double click or right click .reg file > select Merge
4.If prompted, click/tap on Run, Yes (UAC), Yes, and OK to approve the merge.
5.Restart computer to complete the process.