This is a tricky question, I am not sure that it is network or hardware related. While rebuiling a W2K Pro, SP4 with all the patches etc, workstation. I had a serial mouse plugged into the system. The network, has been setup up successfully. I can see the domain, access all mapped drives, connect to the internet etc. The problem that I have is that when I connect a PS2 mouse to the system, I cannot access the network at all. Mapped drives are not accessable, the network shares are unavailable etc. I have uninstalled the PS2 mouse and network card completely and reinstalled both items. If I remove the PS2 mouse and reboot the network is fully active. The problem still persists. The are no conflicts on the system dialog box for both mouse and network card. What could I look at besides rebuilding the system totally.