Unable to Open Adobe Acrobat X Pro or Acrobat Reader

I used to be bale to open PDF files in Adobe Acrobat X Pro but now I cannot. I can still see PDF files with Google Chrome or Internet Explorer, but Abode Reader nor Adobe Acrobat X Pro will open. I can still create PDF file (with other programs) but Adobe Reader and Acrobat X Pro will not open. I can't even open the program to deactiviate the serial number. I tried using the Repair option under Control Panel but that didn't fix the problem. What should I do?

Currently Windows 7, using Creative Suite 6 (comes with In-design, photoshop...etc and Adobe Acrobat X Pro).