September 2012 Problem Unsolved - MissingMethodException: Cannot find requested method.

I get these errors as soon as Unity3D opens…

MissingMethodException: Cannot find requested method.
UnityEditor.AppStatusBar.OnGUI()(at C:/BuildAgent/work/d9c061b1c154f5ae/Editor/Mono/GUI/AppStatusBar.cs:117)

MissingMethodException: Cannot find the requested method.
UnityEngine.GUIUtility.set_hotControl (Int32 value) (at C:/BuildAgent/work/d9c061b1c154f5ae/Runtime/ExportGenerated/Editor/GUIUtility.cs:296)
UnityEditor.ListViewShared+ListViewElementsEnumerator.MoveNext () (at C:/BuildAgent/work/d9c061b1c154f5ae/Editor/Mono/GUI/ListViewShared.cs:474)
UnityEditor.ConsoleWindow.OnGUI () (at C:/BuildAgent/work/d9c061b1c154f5ae/Editor/Mono/ConsoleWindow.cs:420)
System.Reflection.MonoMethod.Invoke (System.Object obj, BindingFlags invokeAttr, System.Reflection.Binder binder, System.Object parameters, System.Globalization.CultureInfo culture)

I just installed the program and since I’m new to it I guess I can’t really tell if it is affecting its functionality, although I’m sure in some way it is. That’s why I’m here, if any of you can help answer I’d appreciate it.

for those who like me have this annoying error how to solve it are the following steps

  1. uninstall the current version of Unity

2)After that download a previous version to your here Download link for previous versions of unity3d - Questions & Answers - Unity Discussions

  1. install it and ENJOY unity as before