Help with a Cyber Cafe Billing Program

I accidentally uninstaled something that makes the cybercafe billing server work... I need to re-install the program but i cant open it cause the computer cant find the program it was made with. What can i do?
I NEED to install the program cause without it i cant keep track of time used on the computer. i need to get it done before my shift is over... i dont want to get in trouble.
let me know if you need more information
oh!
someone told me to restore the computer... how do i do that???

please help!!

 

Assuming you have system restore enabled..

Start>All Programs>Accessories>System Tools>System Restore

If system restore isn't enabled, then you aren't going to be able to do this. It would help if you knew the name of the software. I could probably find it for you, so that you could reinstall it.