With Forge API, whenever I try and load up Minecraft with it installed it doesn't load up. The launcher will open but not the game. I read another article on the web that it doesn't work with Java 8 - do I need to uninstall it? Or is there another way to make them work together?

  • Are you sure it's the problem? Either way you uninstall it the same way you do most programs (if Windows, Start->Search for 'Programs and Features', Find Java 8 and uninstall it. Then, when you download Java again, make sure it's Java 7.
    – Robotnik
    Jan 12 '15 at 3:16
  • @Robotnik: Do you have a reading problem? The question was IF uninstalling java 8 was the correct solution, and why/why not. This looks like a very valid question about the minecraft-forge. Glad it shanodin reworded it so everybody can understand it now.
    – Dorus
    Jan 12 '15 at 9:16
  • @Dorus - Thanks, I needed a dose of snark and sarcasm today. The original version of the question was 'How to uninstall Java 8". Now that it's been edited it is clearer, and I've withdrawn my close vote
    – Robotnik
    Jan 12 '15 at 9:28
  • 2
    Hey folks, don't get nasty. @Robotnik was totally right to VTC the question as it was. It just so happened that I knew of an alternative way to resolve the issue other than downgrading Java.
    – shanodin
    Jan 12 '15 at 13:15
  • 1
    Shanodin's right @Dorus, I apologize for snapping back. I wasn't trying to be mean to Neptune, and I'm all for warm welcomes to the community, but we also have rules as to what is and isn't on topic here. I'm glad that there was a positive solution for this question, and I'm happy to admit I read it wrong initially. We're all human, and that was my mistake today.
    – Robotnik
    Jan 12 '15 at 14:31

If you are using Minecraft Forge version or later

You do not need to do anything. Newer versions of Minecraft Forge have fixed the incompatibility with Java 8. If you are experiencing crashes still with this version of Minecraft Forge or later, it is not related to Java 8.

If you are using an older version of Minecraft Forge

The compatibility problem between Forge and Java 8 comes down to an issue with 1 file. Luckily, some kind soul has created a patch which fixes this problem.

The patch download can be found here on the Minecraft forums. Make sure you get the correct one for the version of Minecraft/Forge you're running.

Once you've downloaded the patch, follow these steps to install:

  1. Navigate to the Forge directory. If you are using Windows you can get there by typing the following into your file browser:

    For Minecraft version 1.6.4: %appdata%\.minecraft\libraries\net\minecraftforge\minecraftforge\

    For Minecraft version 1.7.2: %appdata%\.minecraft\libraries\net\minecraftforge\forge\1.7.2- (or switch 1147 for the Forge version you're using)

    For Minecraft version 1.7.10: %appdata%\.minecraft\libraries\net\minecraftforge\forge\1.7.10-

  1. Open the Forge .jar file using WinRAR or 7zip or whichever program you have for this.
  2. Delete the META-INF file (like the good old days!)
  3. Navigate through the following file path: cpw/mods/fml/relauncher
  4. In there you should find a file called CoreModManager.class - replace this file with the one you downloaded.
  5. You should now be able to play Minecraft! Have fun :)
  • 1
    According the the Post you linked, "Fortunately, later versions of Forge for 1.7.10 correct the issue.", though he doesn't state which versions this is. I'd assume he means later than 1208.
    – MrLemon
    Jan 12 '15 at 9:56
  • @MrLemon The user doesn't say whether they are using 1.7.10 or an earlier version of Minecraft. And as you say, it doesn't state which version of Forge fixes the bug.
    – shanodin
    Jan 12 '15 at 13:14

Just install Java JRE 7, as it should work. Or download Java 8 Update 19 or lower


i have created a image guide to quickly resolve this (forge/java 8)issue

enter image description here

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