Minecraft Forums

Hi, I'm minecraft user.
I play minecraft in Mac OS X 10.9
I want to install mode.
My minecraft version is 1.7.2~1.7.9 any version that doesn't matter, just I use new launcher.
When I try to install mode through current way...
After install, when I press play button in launcher...
Nothing happen... I just could find this error report in development console.


Launching game
Looking for old natives to clean up...
Fatal error launching game. Report this to http://mojang.atlassian.net please!
java.lang.NullPointerException
at net.minecraft.launcher.GameLauncher.cleanOldNatives(GameLauncher.java:515)
at net.minecraft.launcher.GameLauncher.launchGame(GameLauncher.java:360)
at net.minecraft.launcher.GameLauncher.onDownloadJobFinished(GameLauncher.java:693)
at net.minecraft.launcher.updater.download.DownloadJob.popAndDownload(DownloadJob.java:124)
at net.minecraft.launcher.updater.download.DownloadJob.access$000(DownloadJob.java:15)
at net.minecraft.launcher.updater.download.DownloadJob$1.run(DownloadJob.java:94)
at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:471)
at java.util.concurrent.FutureTask.run(FutureTask.java:262)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
at java.lang.Thread.run(Thread.java:744)

IN ANY CASE. ANY VERSION. ANY MODE.
EVEN WHEN I USE CURRENT FORGE JAVA INSTALLER. PLEASE HELP ME.
IT'S COMPLETELY ANNOYING ME.

Does that issue only happen when you try to install mods? If so, it's a problem with Forge or whatever other mod causes it, and you should see them for support.
Please remove the mods, and see if Minecraft will launch. If not, try these steps:

1. Open Terminal (Press Command-Space and type Terminal, press enter. should bring up a white window with black hacker-y text).
2. Run the following command in a terminal:

   mv ~/Library/Application\ Support/minecraft/ ~/Library/Application\ Support/oldminecraft

3. Open Minecraft.

That will put your Minecraft files in another folder, so that Minecraft will re-download its core files, which have probably been messed with by whatever mod you tried installing. Your saves and other information can be retrieved from the "oldminecraft" folder in ~/Library/Application Support.