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Exception in thread "main" java.lang.IncompatibleClassChangeError: Implementing

Posted December 20, 201212 yr

I recently tried to install Forge Universal version 6.4.1 on the 1.4.5 Minecraft server version. But everytime I try to run the server I get this message:

Exception in thread "main" java.lang.IncompatibleClassChangeError: Implementing class

at java.lang.ClassLoader.defineClass1(Native Method)

at java.lang.ClassLoader.defineClassCond(ClassLoader.java:631)

at java.lang.ClassLoader.defineClass(ClassLoader.java:615)

at java.security.SecureClassLoader.defineClass(SecureClassLoader.java:141)

at java.net.URLClassLoader.defineClass(URLClassLoader.java:283)

at java.net.URLClassLoader.access$000(URLClassLoader.java:58)

at java.net.URLClassLoader$1.run(URLClassLoader.java:197)

at java.security.AccessController.doPrivileged(Native Method)

at java.net.URLClassLoader.findClass(URLClassLoader.java:190)

at java.lang.ClassLoader.loadClass(ClassLoader.java:306)

at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:301)

at java.lang.ClassLoader.loadClass(ClassLoader.java:247)

logout

Can someone help me with this problem?

I am on a Mac

Quote

December 20, 201212 yr

How did you install it and how are you running it (e.g. startup script)?

There's an EAQ for a reason. Read it!

"Note that failure to read this will make you look idiotic. You don't want that do you?" -- luacs1998

First rule of bug reports: More information is always better.

Oh, and logs OR IT DIDN'T HAPPEN!!

Quote

December 20, 201212 yr

This typically happens when you have something in there that is for the wrong version of minecraft.

Remove everything including your mods and coremods folder. And start fresh.

I do Forge for free, however the servers to run it arn't free, so anything is appreciated.
Consider supporting the team on Patreon

Quote

December 21, 201212 yr

Author

Bleh, I think I know why... Didn't know 1.4.6 got released and I probably downloaded the 1.4.6 version of the minecraft server.

Anybody have a spare 1.4.5 Minecraft Server.jar (maybe with Forge pre-installed)?

Quote

December 21, 201212 yr

Vanilla 1.4.5 server: http://assets.minecraft.net/1_4_5/minecraft_server.jar

Protip: try and find answers yourself before asking on the forum.

It's pretty likely that there is an answer.

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December 21, 201212 yr

Author

Thanks, I'll try ASAP

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Exception in thread "main" java.lang.IncompatibleClassChangeError: Implementing

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