Minecraft Forums

Okay, so I was making this cool Star Wars/Star Trek Sci-Fi mod for 1.7.10 (Because some mod-makers are idiots and won't update some of the ones I need).. and when I tried to run it, I got this:

[15:07:35] [main/INFO] [GradleStart]: Extra: []

[15:07:36] [main/INFO] [GradleStart]: Running with arguments: [--tweakClass, cpw.mods.fml.common.launcher.FMLServerTweaker, --tweakClass, net.minecraftforge.gradle.tweakers.CoremodTweaker]
[15:07:37] [main/INFO] [LaunchWrapper]: Loading tweak class name cpw.mods.fml.common.launcher.FMLServerTweaker
[15:07:38] [main/INFO] [LaunchWrapper]: Using primary tweak class name cpw.mods.fml.common.launcher.FMLServerTweaker
[15:07:38] [main/INFO] [LaunchWrapper]: Loading tweak class name net.minecraftforge.gradle.tweakers.CoremodTweaker
[15:07:39] [main/INFO] [LaunchWrapper]: Calling tweak class cpw.mods.fml.common.launcher.FMLServerTweaker
[15:07:39] [main/INFO] [FML]: Forge Mod Loader version 7.10.11.1178 for Minecraft 1.7.10 loading
[15:07:39] [main/INFO] [FML]: Java is Java HotSpot(TM) 64-Bit Server VM, version 1.8.0_131, running on Windows 10:amd64:10.0, installed at C:\Program Files\Java\jdk1.8.0_131\jre
[15:07:39] [main/INFO] [FML]: Managed to load a deobfuscated Minecraft name- we are in a deobfuscated environment. Skipping runtime deobfuscation
[15:07:40] [main/INFO] [LaunchWrapper]: Calling tweak class net.minecraftforge.gradle.tweakers.CoremodTweaker
[15:07:40] [main/INFO] [GradleStart]: Injecting location in coremod cpw.mods.fml.relauncher.FMLCorePlugin
[15:07:40] [main/INFO] [GradleStart]: Injecting location in coremod net.minecraftforge.classloading.FMLForgePlugin
[15:07:40] [main/INFO] [LaunchWrapper]: Loading tweak class name cpw.mods.fml.common.launcher.FMLInjectionAndSortingTweaker
[15:07:40] [main/INFO] [LaunchWrapper]: Loading tweak class name cpw.mods.fml.common.launcher.FMLDeobfTweaker
[15:07:40] [main/INFO] [LaunchWrapper]: Loading tweak class name net.minecraftforge.gradle.tweakers.AccessTransformerTweaker
[15:07:40] [main/INFO] [LaunchWrapper]: Calling tweak class cpw.mods.fml.common.launcher.FMLInjectionAndSortingTweaker
[15:07:40] [main/ERROR] [LaunchWrapper]: Unable to launch
java.util.ConcurrentModificationException
at java.util.ArrayList$Itr.checkForComodification(ArrayList.java:901) ~[?:1.8.0_131]
at java.util.ArrayList$Itr.remove(ArrayList.java:865) ~[?:1.8.0_131]
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:?]
at net.minecraftforge.gradle.GradleStartCommon.launch(Unknown Source) [start/:?]
at GradleStartServer.main(Unknown Source) [start/:?]
Java HotSpot(TM) 64-Bit Server VM warning: Using incremental CMS is deprecated and will likely be removed in a future release

Can anyone Help?