Photoshop CS5 not working

Hello

I am having trouble w/ my Photoshop software and was wondering if you can help me resolve it. I previously used Photoshop CS4 and wanted an updgrade so I installed the CS5. However, when I deleted the CS4 software (by using the uninstaller) to allocate more space, I started getting an error message (see photo)

Can someone help me sort out this problem?

Many thanks

Wasma