Minecraft ModLoader Install in Linux

Being a computer geek is kind of fun… unless it’s a holiday weekend and family members continually use you for free technical support.  Of course, when it’s your son, it’s hard to say, “No!”  Besides, I live for technical challenges that need solving with very scant information.

So, on New Years Day, my son was attempting to install ModLoader for Minecraft.  When he had asked, he had already struggled to follow the instructions for some time, and things were NOT going well.

Anyway, it appears that the way that some of the “make-it-easy-to-do-stuff” tools don’t actually do everything right.  Specifically, using “Archive Manager” in Ubuntu Linux to add files to a Java .jar file doesn’t properly work.

So, if you’re trying to follow the install instructions for ModLoader on Linux and your program freezes on the Mojang splash-screen, the .jar file it is likely that your jar file is somehow corrupted.  The best way to add the appropriate files to your minecraft.jar file is to create a new directory and unzip the minecraft.jar file into that directory.  Add the appropriate files.  Zip up the directory again and rename it minecraft.jar.

Make sure to use the -r (recurse subdirectories) when zipping up the jar file again.  Otherwise, the .jar file will still be incomplete.

Here’s a quick transcript of what we did to recreate the minecraft.jar file with the proper files from ModLoader 1.0.0:

A couple of notes – ModLoader.zip was placed in the .minecraft/Downloads directory (a directory specifically created to store minecraft download files like mods and others).

#cd ~/.minecraft/Downloads
#mkdir ModLoader
#cd ModLoader
#cp ../ModLoader.zip .
#unzip ModLoader.zip
#cd ~/.minecraft/bin
#cp minecraft.jar minecraft.orig.jar               #NOTE: Make a backup copy – just in case
#mkdir modloader-workdir
#cd modloader-workdir
#cp ../minecraft.jar .
#unzip minecraft.jar
#rm minecraft.jar
#cp ../../Downloads/ModLoader/* .
#rm -r META-INF #NOTE: This REQUIRED STEP missed in original posting
#zip -r minecraft.zip *
#mv minecraft.zip ../minecraft.jar
#cd ..
#rm -rf modloader-workdir

That will create a new minecraft.jar file with the ModLoader classfiles.  NOTE: You will need to follow these instructions any time MineCraft updates (even if it’s a forced update) – so make sure to keep the ModLoader.zip file around.

Hopefully this will help others, but more importantly, it’ll help me remember what the heck I did when Minecraft gets updated and I need to redo this.