Bootstrap (v5) Current time is Dec 17, 2013 8:07:22 PM System.getProperty('os.name') == 'Mac OS X' System.getProperty('os.version') == '10.9.1' System.getProperty('os.arch') == 'x86_64' System.getProperty('java.version') == '1.6.0_65' System.getProperty('java.vendor') == 'Apple Inc.' System.getProperty('sun.arch.data.model') == '64' Looking for update Downloading: https://s3.amazonaws.com/Minecraft.Download/launcher/ launcher.pack.lzma Got reply in: 937ms Reversing LZMA on /Users/michael/Library/Application Support/minecraft/ launcher.pack.lzma to /Users/michael/Library/Application Support/minecraft/ launcher.pack No update found. Unpacking /Users/michael/Library/Application Support/minecraft/launcher.pack to / Users/michael/Library/Application Support/minecraft/launcher.jar Cleaning up /Users/michael/Library/Application Support/minecraft/launcher.pack Starting launcher. FATAL ERROR: java.lang.NoClassDefFoundError: java/util/concurrent/Delayed at java.lang.Class.forName0(Native Method) at java.lang.Class.forName(Class.java:171) at org.apache.logging.log4j.core.config.plugins.PluginManager.decode(PluginManager.jav a:241) at org.apache.logging.log4j.core.config.plugins.PluginManager.collectPlugins(PluginMana ger.java:152) at org.apache.logging.log4j.core.config.plugins.PluginManager.collectPlugins(PluginMana ger.java:130) at org.apache.logging.log4j.core.pattern.PatternParser.<init>(PatternParser.java: 116) at org.apache.logging.log4j.core.pattern.PatternParser.<init>(PatternParser.java: 102) at org.apache.logging.log4j.core.layout.PatternLayout.createPatternParser(PatternLayout.j ava:183) at org.apache.logging.log4j.core.layout.PatternLayout.<init>(PatternLayout.java: 115) at org.apache.logging.log4j.core.layout.PatternLayout.createLayout(PatternLayout.java: 219) at org.apache.logging.log4j.core.config.DefaultConfiguration.<init>(DefaultConfiguration.ja va:51) at org.apache.logging.log4j.core.LoggerContext.<init>(LoggerContext.java:63) at org.apache.logging.log4j.core.selector.ClassLoaderContextSelector.locateContext(Clas sLoaderContextSelector.java:217) at org.apache.logging.log4j.core.selector.ClassLoaderContextSelector.getContext(ClassLo aderContextSelector.java:114) at org.apache.logging.log4j.core.selector.ClassLoaderContextSelector.getContext(ClassLo aderContextSelector.java:81) at org.apache.logging.log4j.core.impl.Log4jContextFactory.getContext(Log4jContextFactor y.java:83) at org.apache.logging.log4j.core.impl.Log4jContextFactory.getContext(Log4jContextFactor y.java:34) at org.apache.logging.log4j.LogManager.getLogger(LogManager.java:387) at org.apache.logging.log4j.LogManager.getLogger(LogManager.java:322) at net.minecraft.launcher.Launcher.<clinit>(Launcher.java:58) at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method) at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImp l.java:39) at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAcc essorImpl.java:27) at java.lang.reflect.Constructor.newInstance(Constructor.java:513) at net.minecraft.bootstrap.Bootstrap.startLauncher(Bootstrap.java:240) at net.minecraft.bootstrap.Bootstrap.execute(Bootstrap.java:124) at net.minecraft.bootstrap.Bootstrap.main(Bootstrap.java:381) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java :25) at java.lang.reflect.Method.invoke(Method.java:597) at apple.launcher.LaunchRunner.run(LaunchRunner.java:116) at apple.launcher.LaunchRunner.callMain(LaunchRunner.java:51) at apple.launcher.JavaApplicationLauncher.launch(JavaApplicationLauncher.java:52) Caused by: java.lang.ClassNotFoundException: java.util.concurrent.Delayed at java.net.URLClassLoader$1.run(URLClassLoader.java:202) at java.security.AccessController.doPrivileged(Native Method) at java.net.URLClassLoader.findClass(URLClassLoader.java:190) at java.lang.ClassLoader.loadClass(ClassLoader.java:306) at java.lang.ClassLoader.loadClass(ClassLoader.java:247) ... 34 more Please fix the error and restart.