I've often used Windows NT 4.0's Nslookup utility to troubleshoot SMTP mail server problems, but I've recently run into a peculiarity with Windows 2000's Nslookup. Apparently, the Win2K version doesn't query for mail exchanger (MX) records. Under NT 4.0, I can open a command prompt and type

set type=mx

then enter a domain name to see all the MX records for that domain. However, this command doesn't seem to work under Win2K. I've already installed Service Pack 1 (SP1), which didn't help. Why isn't Nslookup working?

I've run into the same problem. Under NT 4.0, the command you describe causes Nslookup to display all the MX records in the domain, as well as the address (A) record for each returned MX record. Under Win2K, however, Nslookup instead displays the name of the default DNS server and basic information (e.g., primary DNS server, zone file serial number, Time to Live—TTL—value) about the DNS domain zone file.

This situation occurs only when the client is a Win2K system using the Win2K version of Nslookup and when the server you're querying is an NT 4.0 DNS server. Under these circumstances, a currently undocumented conflict between these two components causes most Nslookup commands to fail.

Two possible workarounds exist. First, you can use Nslookup's Server command with the name or IP address of a DNS server to change the default DNS server to one that isn't running NT 4.0 DNS. (To make this solution permanent, change the DNS server order in your IP stack so that Nslookup always tries the non­NT 4.0 DNS server first.) Second, you can replace your Win2K system's version of Nslookup with a copy of the NT 4.0 version, which doesn't exhibit this odd behavior.