You can use the “netstat” command from command prompt to determine which program is using any port.
Follow these steps:
1. Click Start, type cmd in the Start Search box, and then press ENTER.
If you are prompted for an administrator password or for a confirmation, type the password, or click Continue.
2. Type netstat –o and hit enter.
This will provide a list of ports, along with the PID (process ID) that has those ports open.
3. To determine what executable is running as a process ID, open Windows Task Manager and switch to the Processes tab.
4. Now click on View->Select Columns.
5. On the screen that opens, make sure "PID (Process Identifier)" is checked and then click OK.
6. Now click on the PID heading to sort the entries by PID.
7. Get the PID numbers from command prompt and verify from task manager.
NOTE: Check only for TCP or UDP protocols as port 80 is TCP/UDP.