Problème lancement modpack Infinity FTB

Bonjour,

j'ai réussi à installer le modpack infinity mais lors du lancement, la console m'affiche ceci :

Exception in thread "main" [09:49:36] [main/INFO] [STDERR]: [java.lang.Throwable$WrappedPrintStream:println:-1]: java.lang.NoClassDefFoundError: scala/collection/Seq
[09:49:36] [main/INFO] [STDERR]: [java.lang.Throwable$WrappedPrintStream:println:-1]: at java.lang.Class.forName0(Native Method)
[09:49:36] [main/INFO] [STDERR]: [java.lang.Throwable$WrappedPrintStream:println:-1]: at java.lang.Class.forName(Unknown Source)
[09:49:36] [main/INFO] [STDERR]: [java.lang.Throwable$WrappedPrintStream:println:-1]: at cpw.mods.fml.relauncher.CoreModManager.loadCoreMod (CoreModManager.java:417)
[09:49:36] [main/INFO] [STDERR]: [java.lang.Throwable$WrappedPrintStream:println:-1]: at cpw.mods.fml.relauncher.CoreModManager.discoverCor eMods(CoreModManager.java:346)
[09:49:36] [main/INFO] [STDERR]: [java.lang.Throwable$WrappedPrintStream:println:-1]: at cpw.mods.fml.relauncher.CoreModManager.handleLaunc h(CoreModManager.java:214)
[09:49:36] [main/INFO] [STDERR]: [java.lang.Throwable$WrappedPrintStream:println:-1]: at cpw.mods.fml.relauncher.FMLLaunchHandler.setupHome (FMLLaunchHandler.java:90)
[09:49:36] [main/INFO] [STDERR]: [java.lang.Throwable$WrappedPrintStream:println:-1]: at cpw.mods.fml.relauncher.FMLLaunchHandler.setupClie nt(FMLLaunchHandler.java:67)
[09:49:36] [main/INFO] [STDERR]: [java.lang.Throwable$WrappedPrintStream:println:-1]: at cpw.mods.fml.relauncher.FMLLaunchHandler.configure ForClientLaunch(FMLLaunchHandler.java:34)
[09:49:36] [main/INFO] [STDERR]: [java.lang.Throwable$WrappedPrintStream:println:-1]: at cpw.mods.fml.common.launcher.FMLTweaker.injectInto ClassLoader(FMLTweaker.java:126)
[09:49:36] [main/INFO] [STDERR]: [java.lang.Throwable$WrappedPrintStream:println:-1]: at net.minecraft.launchwrapper.Launch.launch(Launch.j ava:115)
[09:49:36] [main/INFO] [STDERR]: [java.lang.Throwable$WrappedPrintStream:println:-1]: at net.minecraft.launchwrapper.Launch.main(Launch.jav a:28)
[09:49:36] [main/INFO] [STDERR]: [java.lang.Throwable$WrappedPrintStream:println:-1]: Caused by: java.lang.ClassNotFoundException: scala.collection.Seq
[09:49:36] [main/INFO] [STDERR]: [java.lang.Throwable$WrappedPrintStream:println:-1]: at java.net.URLClassLoader.findClass(Unknown Source)
[09:49:36] [main/INFO] [STDERR]: [java.lang.Throwable$WrappedPrintStream:println:-1]: at net.minecraft.launchwrapper.LaunchClassLoader.find Class(LaunchClassLoader.java:117)
[09:49:36] [main/INFO] [STDERR]: [java.lang.Throwable$WrappedPrintStream:println:-1]: at java.lang.ClassLoader.loadClass(Unknown Source)
[09:49:36] [main/INFO] [STDERR]: [java.lang.Throwable$WrappedPrintStream:println:-1]: at java.lang.ClassLoader.loadClass(Unknown Source)
[09:49:36] [main/INFO] [STDERR]: [java.lang.Throwable$WrappedPrintStream:println:-1]: ... 11


Je ne trouve pas d'où provient l'erreur. Je suis avec java 64 bits et j'ai deja essayer de réinstaller le modpack mais cela ne fonctionne toujours pas.

Merci de bien vouloir m'aider :) .

Problème lancement modpack Infinity FTB