How to change application port
1. Stop the application
2. Open Command Prompt as Admin
3. Go to ManageEngine\ServiceDeskPlus-MSP\bin
4. Invoke command changeWebServerPort.bat [newportnumber] [Protocol http or https]
5. Start the application.
Refer below screenshot
Note : Changing the port will reset the server.xml present under ManageEngine\ServiceDeskPlus-MSP\conf. Hence, if you have applied SSL it would reset it.