Are on the computer several network card configures?
Deactivate for a test the not used network cards, in order to be able to limit the error. For this also virtual network maps cards (e.g. ISDN adapters) must be deactivated. Test the DCOM connection with the Microsoft® demo program: Download: http://download.microsoft.com/download/Winntsrv40/Utility/1.0/WIN98/EN-US/DCOMTest.exe For Windows® XP, you can do this check also with the Network testtool in the Network connection settings.