Could not load file or assembly Microsoft.Practices.EnterpriseLibrary.Configuration.Design

Hello Geeks,     I am using given error "Could not load file or assembly 'Microsoft.Practices.EnterpriseLibrary.Configuration.Design, Version=3.1.0.0, Culture=neutral, PublicKeyToken=null' or one of its dependencies. The system cannot find the file specified." on my server last days. Can anybody have exact !dea how to resolve this critical issue. I have Google the same error then got some tips how that manifest defintion of the assembly not matching the actual reference. Can I have upgrade vesion Version=3.1.0.0 to Version=3.1.0.1 to newer version, please provide me your best suggestions by asap. thanks!