Unable to open my C# project

I'm unable to open my project in Visual Studio 2008. It was developed in C# by my friend. It is showing the this error:

  "Could not find type 'LibrarySystem.ctrlSeparator'.
  Please make sure tha开发者_高级运维t the assembly that contains this type is referenced.
  If this type is a part of your development project, make sure that
  the project has been successfully built. "

Also

  "The variable 'ctrlSeparator1' is either undeclared or was never assigned. "

How do I rectify this problem?

With all respect...the error message tells you everything you need to know...

It's trying to load a control, which does not exist. So either your friend didn't give you the whole project, or he used a Third-party-Component which you don't have.

Obviously your friend used (or wrote himself) a external library.

Ask him to provide you with this assembly, so that you can compile the project.

Either you don't have the complete project or you need to register dll. Make sure you have LibrarySystem.ctrlSeparator in code or assembly. If it is in unmanaged assembly then ask to friend whether it is needed to be registered.