Win NT Server 4.0

I am installing a small LAN within my apartment with 3 computers:
Win ’98 machine
Win ME machine
Win NT server.
Win 98 and ME machines are in a workgroup called “workgroup” and the Win NT server is on its own domain called “Andromeda”. When trying to access the C drive on the Win NT system from the 98 workstation, I get a password prompt for IPC$. I didn’t set or can eliminate this prompt from the NT machine. Can anyone offer some insight? Thanks