Alright. The mods I have installed are too many items, player API, arrows mod, modloader, morebows mod, minecraft forge and optifine. Unfortunately, my minecraft crashes when I try to load it. After isolating each mod, I have found that the problem was the minecraft forge. Here's the crash report *** MagicMinecraftLauncher 1.0.0 *** 
java.lang.IncompatibleClassChangeError: Implementing class 
    at java.lang.ClassLoader.defineClass1(Native Method) 
    at java.lang.ClassLoader.defineClass(Unknown Source) 
    at java.security.SecureClassLoader.defineClass(Unknown Source) 
    at java.net.URLClassLoader.defineClass(Unknown Source) 
    at java.net.URLClassLoader.access$100(Unknown Source) 
    at java.net.URLClassLoader$1.run(Unknown Source) 
    at java.net.URLClassLoader$1.run(Unknown Source) 
    at java.security.AccessController.doPrivileged(Native Method) 
    at java.net.URLClassLoader.findClass(Unknown Source) 
    at java.lang.ClassLoader.loadClass(Unknown Source) 
    at java.lang.ClassLoader.loadClass(Unknown Source) 
    at magic.launcher.Launcher.main(Unknown Source) 
  
I was using magic launcher at that time. Please inform this was caused by forge, and how to fix it if so. Thanks