Cant start minecraft

[Critical31213]

I wanted to play All The Mods pack, so I downloaded it from curse. I started minecraft and clicked play... and there is a problem, minecraft dont start and I get a log:
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2016-09-27 21:56:17,495 WARN Unable to instantiate org.fusesource.jansi.WindowsAnsiOutputStream
[21:56:17] [main/INFO]: Loading tweak class name net.minecraftforge.fml.common.launcher.FMLTweaker
[21:56:17] [main/ERROR]: Unable to launch
java.lang.ClassNotFoundException: net.minecraftforge.fml.common.launcher.FMLTweaker
at java.net.URLClassLoader.findClass(Unknown Source) ~[?:1.8.0_91]
at java.lang.ClassLoader.loadClass(Unknown Source) ~[?:1.8.0_91]
at sun.misc.Launcher$AppClassLoader.loadClass(Unknown Source) ~[?:1.8.0_91]
at java.lang.ClassLoader.loadClass(Unknown Source) ~[?:1.8.0_91]
at net.minecraft.launchwrapper.LaunchClassLoader.findClass(LaunchClassLoader.java:106) ~[launchwrapper-1.12.jar:?]
at java.lang.ClassLoader.loadClass(Unknown Source) ~[?:1.8.0_91]
at java.lang.ClassLoader.loadClass(Unknown Source) ~[?:1.8.0_91]
at java.lang.Class.forName0(Native Method) ~[?:1.8.0_91]
at java.lang.Class.forName(Unknown Source) ~[?:1.8.0_91]
at net.minecraft.launchwrapper.Launch.launch(Launch.java:98) [launchwrapper-1.12.jar:?]
at net.minecraft.launchwrapper.Launch.main(Launch.java:28) [launchwrapper-1.12.jar:?]
Java HotSpot(TM) 64-Bit Server VM warning: ignoring option PermSize=256m; support was removed in 8.0
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Can someone help me with it?

 

[Kraise_]

Make sure you have at least 5gb of RAM assigned.

 

[KookyKraftMC]

Reinstall, curse did not fully download Forge.