Can't connect to server

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    I created an assembly on fabric, added mods to the Aternos server, but when I try to access the server, an error appears:


    Internal Exception: io.netty.handler.codec.DecoderException:

    java lang.Nullpointerexception: Cannot invoke "java.util.function.Supplier.geto"

    because the return value of "java.util Map.get Object)" is null



    what to do?

    Your title says "Do not use an Aternos server for fabric assembly".

    The problem you are having has nothing to do with the server host you use.

    I'll change it.


    Share the server log using the share button on the log page.

    Also share your client log:

    1. open your minecraft installation path

    (enter %appdata%/.minecraft in the file explorer )

    2. open the logs folder

    3. open the "latest" or "latest.log" file with a text editor

    4. copy and paste the content of the file to https://mclo.gs/

    5. send the link here

  • Adriel

    Changed the title of the thread from “Do not use an Aternos server for fabric assembly” to “Can't connect to server”.