Internal server error when I try to log on from my Windows PC

Plex Media Server
1

My Nvidia Shield and Android phone are not having any issues, only my Windows desktop PCs - both the 6-or-7-year-old i5 windows PC that hosts my server and the newer one I use to access it.

Server Version#: not sure but fairly recently updated
Player Version#:

2

Just unlinked Tidal from my Plex account and was able to log in fine

3

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