This is what it said[19:20:17] [main/INFO] [LaunchWrapper]: Loading tweak class name cpw.mods.fml.common.launcher.FMLTweaker

[19:20:17] [main/INFO] [LaunchWrapper]: Using primary tweak class name cpw.mods.fml.common.launcher.FMLTweaker

[19:20:17] [main/INFO] [LaunchWrapper]: Calling tweak class cpw.mods.fml.common.launcher.FMLTweaker

[19:20:17] [main/INFO] [FML]: Forge Mod Loader version 7.10.85.1277 for Minecraft 1.7.10 loading

[19:20:17] [main/INFO] [FML]: Java is Java HotSpot Client VM, version 1.7.0_71, running on Windows 7:x86:6.1, installed at C:\Program Files (x86)\Java\jre7

[19:20:17] [main/WARN] [FML]: The coremod CustomSteve.LoadingPlugin does not have a MCVersion annotation, it may cause issues with this version of Minecraft

[19:20:17] [main/INFO] [LaunchWrapper]: Loading tweak class name cpw.mods.fml.common.launcher.FMLInjectionAndSortingTweaker

[19:20:17] [main/INFO] [LaunchWrapper]: Loading tweak class name cpw.mods.fml.common.launcher.FMLDeobfTweaker

[19:20:17] [main/INFO] [LaunchWrapper]: Calling tweak class cpw.mods.fml.common.launcher.FMLInjectionAndSortingTweaker

[19:20:17] [main/INFO] [LaunchWrapper]: Calling tweak class cpw.mods.fml.common.launcher.FMLInjectionAndSortingTweaker

[19:20:17] [main/INFO] [LaunchWrapper]: Calling tweak class cpw.mods.fml.relauncher.CoreModManager$FMLPluginWrapper

[19:20:19] [main/INFO] [FML]: Found valid fingerprint for Minecraft Forge. Certificate fingerprint e3c3d50c7c986df74c645c0ac54639741c90a557

[19:20:19] [main/ERROR] [FML]: The minecraft jar file:/C:/Users/Owner/AppData/Roaming/.minecraft/versions/1.7.10-Forge10.13.2.1277/1.7.10-Forge10.13.2.1277.jar!/net/minecraft/client/ClientBrandRetriever.class appears to be corrupt! There has been CRITICAL TAMPERING WITH MINECRAFT, it is highly unlikely minecraft will work! STOP NOW, get a clean copy and try again!

[19:20:19] [main/ERROR] [FML]: For your safety, FML will not launch minecraft. You will need to fetch a clean version of the minecraft jar file

[19:20:19] [main/ERROR] [FML]: Technical information: The class net.minecraft.client.ClientBrandRetriever should have been associated with the minecraft jar file, and should have returned us a valid, intact minecraft jar location. This did not work. Either you have modified the minecraft jar file (if so run the forge installer again), or you are using a base editing jar that is changing this class (and likely others too). If you REALLY want to run minecraft in this configuration, add the flag -Dfml.ignoreInvalidMinecraftCertificates=true to the 'JVM settings' in your launcher profile.

Exception in thread "main" [19:20:19] [main/INFO] [sTDERR]: [java.lang.Throwable$WrappedPrintStream:println:-1]: java.lang.ExceptionInInitializerError

[19:20:19] [main/INFO] [sTDERR]: [java.lang.Throwable$WrappedPrintStream:println:-1]: at cpw.mods.fml.common.asm.FMLSanityChecker.call(FMLSanityChecker.java:159)

[19:20:19] [main/INFO] [sTDERR]: [java.lang.Throwable$WrappedPrintStream:println:-1]: at cpw.mods.fml.common.asm.FMLSanityChecker.call(FMLSanityChecker.java:39)

[19:20:19] [main/INFO] [sTDERR]: [java.lang.Throwable$WrappedPrintStream:println:-1]: at cpw.mods.fml.relauncher.CoreModManager$FMLPluginWrapper.injectIntoClassLoader(CoreModManager.java:126)

[19:20:19] [main/INFO] [sTDERR]: [java.lang.Throwable$WrappedPrintStream:println:-1]: at net.minecraft.launchwrapper.Launch.launch(Launch.java:115)

[19:20:19] [main/INFO] [sTDERR]: [java.lang.Throwable$WrappedPrintStream:println:-1]: at net.minecraft.launchwrapper.Launch.main(Launch.java:28)

[19:20:19] [main/INFO] [sTDERR]: [java.lang.Throwable$WrappedPrintStream:println:-1]: Caused by: java.lang.NullPointerException

[19:20:19] [main/INFO] [sTDERR]: [java.lang.Throwable$WrappedPrintStream:println:-1]: at cpw.mods.fml.common.Loader.<init>(Loader.java:182)

[19:20:19] [main/INFO] [sTDERR]: [java.lang.Throwable$WrappedPrintStream:println:-1]: at cpw.mods.fml.common.Loader.instance(Loader.java:160)

[19:20:19] [main/INFO] [sTDERR]: [java.lang.Throwable$WrappedPrintStream:println:-1]: at cpw.mods.fml.common.FMLCommonHandler.<init>(FMLCommonHandler.java:87)

[19:20:19] [main/INFO] [sTDERR]: [java.lang.Throwable$WrappedPrintStream:println:-1]: at cpw.mods.fml.common.FMLCommonHandler.<clinit>(FMLCommonHandler.java:77)

[19:20:19] [main/INFO] [sTDERR]: [java.lang.Throwable$WrappedPrintStream:println:-1]: ... 5 more

 

 

Did you install any jar mods (optifine, fps++)?