Fport is a very handy tool to determine which ports are mapped to which process.
You can download it here
From Foundstone (creators of tool):
“fport reports all open TCP/IP and UDP ports and maps them to the owning application. This is the same information you would see using the ‘netstat -an’ command, but it also maps those ports to running processes with the PID, process name and path. Fport can be used to quickly identify unknown open ports and their associated applications.”
Usage: C:\>fport FPort v2.0 - TCP/IP Process to Port Mapper Copyright 2000 by Foundstone, Inc. http://www.foundstone.com Pid Process Port Proto Path 392 svchost -> 135 TCP C:\WINNT\system32\svchost.exe 8 System -> 139 TCP 8 System -> 445 TCP 508 MSTask -> 1025 TCP C:\WINNT\system32\MSTask.exe 392 svchost -> 135 UDP C:\WINNT\system32\svchost.exe 8 System -> 137 UDP 8 System -> 138 UDP 8 System -> 445 UDP 224 lsass -> 500 UDP C:\WINNT\system32\lsass.exe 212 services -> 1026 UDP C:\WINNT\system32\services.exe The program contains five (5) switches. The switches may be utilized using either a '/' or a '-' preceding the switch. The switches are; Usage: /? usage help /p sort by port /a sort by application /i sort by pid /ap sort by application path For updates visit: www.foundstone.com
If you run in to issues running it on server 2003, please run in xp compatibility mode as admin from command prompt