“Port 5000 is in use” when opening an exam on the server

ExamQR Exam always uses TCP port 5000 on the server computer for candidate connections. Only one program can use a port at a time.

How you recognise it

• When you open an exam, a window titled “Port 5000 is in use” says “An older ExamQR instance is still running (process ExamQR.Server, PID 1234) and holding port 5000. Close the old process and try again?” or “Another application is using port 5000 (process name, PID 1234). Close that application and try again.”
• Under System status on the dashboard: “Port 5000: in use by 'name'”

Likely causes

• An earlier ExamQR Exam window did not close completely, or a second copy is running.
• Another program on this computer listens on port 5000 (for example a local web server, development tool or service).

Fix it

1. If the message names an older ExamQR instance, click Close old process. If you then see “The old process was closed but port 5000 is still busy. Please try again in a moment.”, wait a few seconds and open the exam again.
2. If another program holds the port, the message gives its name and process number (PID). Close that program. On Windows you can also open Task Manager, go to Details, find the PID and choose End task (only if you know what the program is). On Linux, ss -ltnp | grep 5000 shows which process uses the port.
3. If you are not sure what the program is, restart the computer and open ExamQR Exam before other programs.
4. If that program must keep running on this computer, run the exam server on another computer: the port cannot be changed.

If it still doesn't work

Report the problem with a screenshot of the message, including the program name and PID it shows.