After playing on a server for a long time, I was disconnected with this error message:

Internal Exception: io.netty.handler.codec.DecoderException: Badly compressed packet - size of 61 is below server threshold of 256

I have never seen this error before. I tried to connect to the server again and it gave me the standard Invalid Session. Restarting my game allowed me to reconnect. I am playing Vanilla 1.11, and I believe that the server had only a few plugins.

What caused this error, and how can I prevent it from happening again?

EDIT: This happened again on the same server with size of 5.

  • I'm not sure how you'd go about solving this issue, but the server is sending you a 61 byte packet, when the minecraft client always expects servers to send packets with at least 256 bytes. – Ted Brownlow Dec 1 '16 at 3:34
  • I'd think that there might be a bug with some custom networking code from one of the few plugins. Maybe it implements custom scoreboard handling, or displays boss bars for something else than bosses. Just a guess tho. – 1Darco1 Dec 1 '16 at 14:04
  • @1Darco1 The server is trying to be as vanilla as possible, so the few plugins are for trading, chat channels, &c. AFAIK they don't really have any resource-heavy plugins. – rivermont - Will B. Dec 1 '16 at 14:54
  • It doesn't have to be any resource-heavy plugin causing the error. A trading plugin opening a GUI to trade in could be enough. Because there are checksums and stuff in place to ensure it's not a poor connection which simply cut the packet short so the last 195 bytes didn't reach you, I would suggest speaking to an admin or preferably a developer on the server about the issue. – 1Darco1 Dec 1 '16 at 16:18

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Browse other questions tagged or ask your own question.