I'm unable to join my server! I receive a java.io.IOException with a 503 error...what is the problem?
If you have received a java.io.IOException with a 503 error, unfortunately, we are unable to assist with this issue. An IO error with the HTTP code 503 means the Mojang session servers are down.
When the session servers are down, you may be able to log into Minecraft itself, but you'll be unable to join any server with online mode enabled as that server will need to authenticate the user's Minecraft name and will be unable to.
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