How to solve problem: System.IO.FileLoadException was unhandled by user code HResult=-2146234304?

Solution:
Make sure you get latest version WebGrease 1.6

Full error message:
System.IO.FileLoadException was unhandled by user code   HResult=-2146234304
  Message=Could not load file or assembly 'WebGrease, Version=1.5.1.25624, Culture=neutral, PublicKeyToken=31bf3856ad364e35' or one of its dependencies. The located assembly's manifest definition does not match the assembly reference. (Exception from HRESULT: 0x80131040)
  Source=System.Web.Optimization
  FileName=WebGrease, Version=1.5.1.25624, Culture=neutral, PublicKeyToken=31bf3856ad364e35
  FusionLog==== Pre-bind state information ===
LOG: DisplayName = WebGrease, Version=1.5.1.25624, Culture=neutral, PublicKeyToken=31bf3856ad364e35
 (Fully-specified)



Reference:
Install-Package Microsoft.AspNet.Web.Optimization
Update-Package WebGrease
Uninstall-Package Microsoft.AspNet.Web.Optimization
Uninstall-Package WebGrease
Install-Package Microsoft.AspNet.Web.Optimization
Update-Package WebGrease
http://forums.asp.net/t/1939632.aspx?cannot+load+webgrease+due+to+mismatched+manifest