W2000 can’t access shared folders on DOS

My Windows 2000 computer cannot access shared files on a MSDOS computer with the Windows for Workgroups update. I have installed TCP/IP, Netbeui, Client for Microsoft networks, and File and Folder sharing on the Win2000 machine.

Other computers on the network, Win95, Win98, WinME and NT4, can access the DOS computer without any problems.

Any ideas?