xpilot says: Xpilot unable to connect to xplane please make sure x plane is running

when I open xpilot it tells me this: Xpilot unable to connect to xplane please make sure x plane is running, even though xplane is active and therefore won’t let me connect. How can I do to solve?

Have you followed all steps from the installation guide? xPilot for VATSIM?
Do you see the xPilot menu entry in X-Plane?

I have been using xpilot for almost a year and it has never given me any problems, only yesterday was bugged. Anyway, I fixed it by reinstalling it. If it happens again, would you know a solution for this problem to avoid having to reinstall everything?
Thank you

Typically this is caused by either antivirus or firewall blocking the connection to X-Plane. There are several solutions that can be found in the FAQ section of the xPilot Documentation website.