error code 20

I am recieving an error code 20 from Navision. It tells me that NetBios can not find the computer name. This only occurs when TCP/IP is installed. Works fine without TCP/IP. Using NT 4.0 SP 6a. and running a DHCP server from an ICS Win98 machine. Any one know what this might be?

Try to change the protocol numbers so netbios is the first protocol on the server, and make sure that netbios is default protocol on the clients. JH