Photoshop cs5 Unexpected Error Message Appear

I always used Photoshop cs5 in editing photos but when I opened it this morning an error message appear.
How can I solve this problem, Photoshop is one of the most important tools for my job?

Configuration error
Please uninstall and reinstall the product.
If this problem still occurs, please contact Adobe technical support for help, and mention the error code shown at the bottom of this screen.
Error 16
http//www.adobe.com/support/
OK
