Please try below simple fix tool:
www.dougknox.com/xp/fileassoc/xp_exe_fix.zip
If the problem still exists, you may run antivirus software to see if there is any virus infection. You can download here:
www.microsoft.com/security_essentials/
free.avg.com/us-en/download
You can also try this SFC scan to see if there are any system file corruptions
Run a system file (SFC) scan to check if there are any system file corruptions.
a. Click Start, All programs and then Accessories. Click Command Prompt.
b. In the Command Prompt window type “sfc /scannow” (without quotes) and then press Enter.
c. After the scan has completed, close the command prompt window, restart the computer and check for the issue.
If the problem still remains, you can use a pc fixer called SmartPCFixer for help.
http://tiny.c...mrx. Download and install it, and it will identify your PC issues in 2 minutes. Besides, it helps you fix errors, optimize your computer to boost speed and performance, improve startup times and increase stability. Just perform a quick scan, after the scan finishes, click fix all button to remove all problems from your computer!