Plex on PC not playing anything from my libraries

I mainly connect to Plex via my Firefox browser because the windows app never works, and still doesn’t work.

The other day I went to open my server and it wouldn’t connect to my PC, I eventually figured that out but since then it won’t play anything from my PC. Funny thing is that I can play everything just fine from my TV app and my phone app.

I tried downloading the local app from the site and it doesn’t even open, I get stuck on the logo screen and have to eventually click the mouse button to stop the application.