My Xbox Live parties refuse to work on PC.

I have tried that but nothing. Also it's not a laptop

Please follow the troubleshooting steps mentioned in the following to update your windows: Troubleshoot Xbox Game Bar on Windows 10 | Xbox Support

It would also help to perform a quick boot on your laptop by following the steps mentioned here: How to perform a clean boot in Windows (microsoft.com)

Hey, I just spent the last few days with the same issue. I came across your post while looking and have since found a fix for me so hopefully it works for you. Under windows security (you can access this from the hidden icons on task bar) i had a notification saying app and browser control were set to off or something like that. Try ticking that so it's all green checks. Let me know if it helps!

Did you reset the router, or did you reboot it? If you did an actual reset, the connection settings have all been changed back to default, including passwords you had stored. You may have to go back into the router settings through your computer and optimize
them again.

I had a similar issue with Ticket To Ride in the Xbox app on PC. Just refused to update - I uninstalled the game, restarted my PC then downloaded it all again and it worked like a treat. Maybe try that?