Can't Get Past Server Selection

[Sinphera]

Hello, I recently tried logging into P99 (Green specifically) and was able to get to the server selection screen just fine. I tried to log in, and got the message "an unknown error has occurred while trying to join the server".

I have tried restarting my computer, but the message remains. The ironic thing is that I was able to play just fine hours earlier, and haven't altered my game in any way that I know of. I didn't even turn off my computer (save for the part I restarted my computer to see if it would help me reconnect). Does anyone know what is causing this? Has this happened to anyone else before?

Any help would be greatly appreciated.

[Sinphera]

Nevermind. It suddenly just started working. Well, not suddenly.

I logged in again after posting this, and it took me to a character selection with no characters on it. I exited, and then re-entered into P99 Green and was suddenly able to get back on fully without issue.

I would still like to know what could have caused this, since I haven't actually done anything on my end that would prompt it to randomly cause errors.