Make sure “file and printer sharing” is enabled on the client you are joining. This is not enabled by default on server 2003.
Need to precreate machine name in domain controller, rename your machine to this name then reboot.
Need to make sure dns can resolve domain controllers (use “nslookup domaincontroller” to get the IPs of the domain controllers if you want to ping them).
Set the DNS suffixes to the domain suffixes in tcpip settings, one of these will more than likely be the domain name itself. To make sure these are used check “Append these DNS suffixes (in order)”.
You need permission to add to the domain, make sure you have it.