Hi, I've stupidly allowed my friend to download my cs3 program for her to do her project and now i've found that my license has 'stopped working'.
I think she has registered the product under her name, while i,havent got to doing that.
SO does anyone know what to do to get my license back? Will making her uninstall the program simply do the trick?
You're talking about several different issues here.
The "licensing has stopped working" problem you're experiencing is most likely not related to your friend using your software (which, by the way, you are now allowed to do). You did not provide any substantial information, but it seems like a technical problem with the licensing service on your machine. You can either call Adobe Tech Support or try looking in Adobe's KnowledgeBase, or here in the forums for a solution.
About the registration - If your friend registered the product under her name while you are the legal owner, I think you should contact Adobe Customer Service. They will probably ask you for a proof of purchase and then will fix this problem for you. Otherwise, just ask your friend to log into her Adobe account and change the details to yours.