I have a WinNT4 BDC SP6, last Sat morning, after I entered
Ctrl+Alt+Del and typed in correct user and password, it poped up a
message box saying "Please wait while network is closing...." and then
rolled back to the Logon (Ctrl+Alt+Del) page.

I have tried the following,

1. Hard Reset
2. VGA Mode
3. using command "NetDom BDC PC_BDC /reset" at PDC

Same result happens. The Mapping drive is normal, workstation can see
the server file.
What can I do next, I don't want to reinstall the whole system.

Please HELP!