I would love to get this to work but it isn't could you help. Using a fresh copy of windows sp2 and it wouldn't slip in: WMP11Slipstreamer v0.991 Detected source: Windows™ XP Professional SP2 System.Exception: Delta API failed to apply patch "_sfx_0010._p" to the file "update.exe". ---> System.ComponentModel.Win32Exception: Unknown error (0xc00e4102) --- End of inner exception stack trace --- at WMP11Slipstreamer.Backend.NativeExtractHotfix(String hotfixInstaller, String destinationPath) at WMP11Slipstreamer.Backend.ExtractWMP11Installer() at WMP11Slipstreamer.MainGUI.workerMethod(Object addonSettings) Deleting "C:\XPCD\i386\wmp11temp"... FAILED! An exception occurred while attempting to delete the temporary folder to revert the changes done to the source. System.UnauthorizedAccessException: Access to the path '_sfx_.dll' is denied. at System.IO.Directory.DeleteHelper(String fullPath, String userPath, Boolean recursive) at System.IO.Directory.Delete(String fullPath, String userPath, Boolean recursive) at WMP11Slipstreamer.ErrorForm..ctor(Exception ex, Boolean critical, String tempFolder, String osString, String hotfixList) Thanks. Tom