Most likely you refer to {429CAD59-35B1-4DBC-BB6D-1DB246563521} which is the name of a folder/directory in Windows system folders program/application data for (legacy) program files (x86) 32 bits. Do not mess with it, many things may go wrong if you do. Remember that 64 bits os like W7 still handle many 32 bits programs like MS Office, internet Explorer or iTunes.