The Internal Exception Java.IO.IOException error usually occurs when you launch Minecraft, or when the game is underway. This error can be caused by a number of different things.

Having trouble with this error in Minecraft? Here are ways to fix it.

If you encounter a missing profile public key error, you may want to close down your game and launcher and run it again in vanilla before re-connecting to a server.

If you see Failed to connect to the server, Connection timed out no further information error on Minecraft, this guide has working solutions to fix it.

Want to know how to set up a Minecraft server with your friends? Here's all you need to know with step-by-step instructions.