MatthewGB

The code was outdated. I had already changed that, it's something else causing the problem.

FML even told you what to do in the error! [embed=425,349][16:53:20] [Client thread/ERROR]: FML has detected a mod that is using a package name based on 'net.minecraft.src' : net.minecraft.src.FMLRenderAccessLibrary. This is generally a severe programming error. There should be no mod code in the minecraft namespace. MOVE YOUR MOD! If you're in eclipse, select your source code and 'refactor' it into a new package. Go on. DO IT NOW! [16:53:20] [Client thread/ERROR]: FML has detected a mod that is using a package name based on 'net.minecraft.src' : net.minecraft.src.Start. This is generally a severe programming error. There should be no mod code in the minecraft namespace. MOVE YOUR MOD! If you're in eclipse, select your source code and 'refactor' it into a new package. Go on. DO IT NOW![/embed]

First of all, "AL lib: (EE) alc_cleanup: 1 device not" happens every time you close minecraft. The only seemingly possible reason for that error is because you're done something to the main classes. If you haven't started modding that JAR you should renew it. Make sure you're using the right forge for 1.7. You also seem quite new to modding. If you're using forge you should (almost) never edit main classes. Always use the API that forge gives you and make new classes. Google some tutorials on how to do stuff.

I did! I looked everywhere and I can't find TileEntityFurnace in any of my classes!

I don't know which class to give you...

Just tested it again, now it crashes with the same error.

Check the "onUpdate()" (or something similar) method of the item for anything unexpected.

Fixed one problem and made another . Now when I click on the block nothing happens. I'll add some more code in a min. Thanks anyway!

When I open the GUI of my custom furnace on MC 1.6.4, the game crashes with the following stacktrace: [embed=425,349]java.lang.ClassCastException: net.minecraft.tileentity.TileEntityFurnace cannot be cast to MatthewGB.MoarOres.TileEntityEFurnace 2014-02-22 16:37:36 [iNFO] [sTDOUT] at MatthewGB.MoarOres.MoarOresFurnace.onBlockActivated(MoarOresFurnace.java:138)[/embed] The block's class: TileEntityEFurnace Class: Anyone know how to fix this error?