Unknown Error Occurred While Trying to Join that Server Message

[4WOFURY]

Happened to me last night.

After trying several times on several accounts and several different servers, I rebooted.

Upon restart, still the same error message, several times, on several accounts, on every server.

Walked away for about 10 minutes, came back, and it was fine.

I was talking to people were in game, through TS, so I know the server wasn't down.