How to deactivate Studio 2014 FL+ without opening the program?

I got an error today while trying to open SDL Studio 2014 FL Plus: "An unexpected error has occurred while loading application plug-ins".

I tried all the proposed solutions with renaming and deleting xmls, renaming folders, etc. but nothing works.

I need to uninstall the program, but I don't know how to deactivate its license since i can't open it.

Any ideas?

thanks

evi