Put the summary of the bug you're having here
What I expected to happen was...:
Start normally
What actually happened was...:
Crash
Steps to Reproduce:
1. Put a step by step guide on how to trigger the bug here
2. ...
3. ...
Comments 2
Incomplete without a crash report from ([minecraft/crash-reports/crash-<DATE>-client.txt|http://hopper.minecraft.net/help/finding-minecraft-data-folder]). Please attach it so that we can diagnose your issue.
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This has happened on my Mac before, I just restarted my computer and it was fixed, try that. If not, reinstall Java unless you have the new launcher.