All Microsoft critical updates thru 01/09/2006 have been tested and approved for use on computers/servers running SmartCAD with the exception of SP1 for Windows Server 2003. Testing for Server 2003 SP1 is ongoing. Check this page for updated information. The following operating systems were tested for all other updates: Windows 2000 Professional, Windows XP Professional, Windows 2000 Server, Windows Server 2003.