If the Internet Mail Service fails to start, check the HOSTS file. The Internet Mail Service server must know each target server. The hosts file is Winnt\System32\Config\Etc\Hosts. If you are using DNS for your Internet Mail Service name resolution, then use a command prompt and the NSLOOKUP TCP/IP utility to determine if you are having DNS problems. More documentation of the NSLOOKUP command can be found by typing NSLOOKUP, waiting for the > NSLOOKUP prompt, then typing help.