I did a fresh version of the jar and .minecraft I downloaded from the launcher  the game launcher goes away but the game never shows up

 

Game output

 

 

[02:06:53] [main/INFO] [LaunchWrapper]: Loading tweak class name cpw.mods.fml.common.launcher.FMLTweaker

[02:06:53] [main/INFO] [LaunchWrapper]: Using primary tweak class name cpw.mods.fml.common.launcher.FMLTweaker

[02:06:53] [main/INFO] [LaunchWrapper]: Calling tweak class cpw.mods.fml.common.launcher.FMLTweaker

[02:06:53] [main/INFO] [FML]: Forge Mod Loader version 7.10.18.1180 for Minecraft 1.7.10 loading

[02:06:53] [main/INFO] [FML]: Java is Java HotSpot 64-Bit Server VM, version 1.8.0_20, running on Windows 8.1:amd64:6.3, installed at C:\Program Files\Java\jre1.8.0_20

[02:06:53] [main/INFO] [LaunchWrapper]: Loading tweak class name cpw.mods.fml.common.launcher.FMLInjectionAndSortingTweaker

[02:06:53] [main/INFO] [LaunchWrapper]: Loading tweak class name cpw.mods.fml.common.launcher.FMLDeobfTweaker

[02:06:53] [main/INFO] [LaunchWrapper]: Calling tweak class cpw.mods.fml.common.launcher.FMLInjectionAndSortingTweaker

[02:06:53] [main/ERROR] [LaunchWrapper]: Unable to launch

java.util.ConcurrentModificationException

  at java.util.ArrayList$Itr.checkForComodification(Unknown Source) ~[?:1.8.0_20]

  at java.util.ArrayList$Itr.remove(Unknown Source) ~[?:1.8.0_20]

  at net.minecraft.launchwrapper.Launch.launch(Launch.java:117) [launchwrapper-1.9.jar:?]

  at net.minecraft.launchwrapper.Launch.main(Launch.java:28) [launchwrapper-1.9.jar:?]

[/spolier]

 

log

 

 

http://pastebin.com/Qz9iXn8U

 

 

 

 

 

update forge