I'm trying to go onto some Minecraft servers today, but it never works. It just pops up with

Internal Exception: io.netty.handler.timeout.ReadTimeoutException

I'm new to Minecraft, so I don't really know what this means. Any help?

  • 1
    The most obvious answer is a network problem. If it's a server you know is running and accepting connections, I'd check that you're not behind a firewall that is preventing connections (i.e. a school/university network). – TZHX Oct 26 '13 at 22:05
  • This error message has been showing up for many people who updated to 1.7.2. It's not entirely due to non-updated servers, though, it seems to be an internal error. My fiance and I played on our server all morning this morning, and upon attempting to log in right now it reads that error and refuses to connect him to our server, though it is running 1.7.2. – user58310 Oct 27 '13 at 10:01

You are running Minecraft 1.7.2 and the server you're connecting to is not. Not only is connecting to a server with a mismatched client currently impossible, but the 1.7.2 update brought with it some minor networking protocol changes, resulting in some new and "interesting" (read as "not very informative") error messages, like the one you got.

You can continue playing on that server by either waiting for them to update to 1.7.2, or by setting up a 1.6.4 profile in your Minecraft Launcher:

  1. Open the launcher, don't click "Play" yet
  2. Click "New Profile"
  3. In the Use Version box, choose release 1.6.4
  4. (optional) Check the box beside Game Directory and add something to the end of the line, like 1.6.4. (This optional step is only necessary if you want to prevent accidentally opening one of your 1.7.2 single-player worlds in 1.6.4, which will corrupt the save. It's not required to allow connecting to 1.6.4 servers. This will also keep your new and old server lists separate.)
  5. Click Save profile

When you want to play on a 1.6.4 server, choose the 1.6.4 profile before clicking "Play"; and when you want to play the latest-and-greatest version of Minecraft either singleplayer or on updated servers, choose your default profile.

† I'm only making an educated guess that the server you're trying to connect to is 1.6.4, so adjust these instructions as necessary if I got that wrong. However, it's a pretty safe guess: you were playing on that server just fine before your client did the automatic update to 1.7.2, it sounds like, and that means you were running and successfully connecting with the previous stable version of 1.6.4.

I only suspected that it was a version mismatch, so I did some science to confirm it. I know you are using the 1.7.2 client because the io.netty in that error message is part of the new networking protocol changes in 1.7.2, but I wasn't sure if this was a bug in the update, or if it was the "normal" error message when connecting to an older server.

I downloaded the 1.6.4 and 1.7.2 servers and tried to connect to each of them with the 1.7.2 client. This is what I got when I tried to connect to the 1.6.4 server:

Failed to connect to the server: Internal exception: io.netty.handler.timeout.ReadTimeoutException

Exactly the same error you got, which is confirmation enough to my mind.

For completeness, this is what I got when I connected to the 1.7.2 server with the 1.7.2 client:

A normal starting-out view of a Minecraft world

A working connection! ...Though, damn, stuck on another island.

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