Don t Write User Data to HKLM
As with writing to \Program Files, writing to HKEY_LOCAL_MACHINE is also not recommended for user application information because the ACL on this registry hive allows users (actually, Everyone) read access. This is the second reason so many applications ported from Windows 95 to Windows NT and later require the user to be an administrator. If you must store data for the user in the registry, store it in HKEY_CURRENT_USER, where the user has full control.