Port is already used !

You can simply try and change the port the server will be on to something like 7575 or whatever comes in your mind, to do this you have to:
1) Go to EMU_EFT_FOLDER\Aki_Data\Server\configs and find http.json
2) Open the file with your favorite text editor and find port setting (you'll see it).
3) Change the port, for example 7575 as mentioned
4) Save it and close
5) Now open your SPT Server and Launcher and don't forget to change the port in launcher settings to the one you set previously!
6) Ta-da!