Adding reference to dll

I tried to add the to System.Windows.Forms.dll and other dlls from the add reference menu, but got an error saying:

'A reference to System.Windows.Forms.dll could not be added.Converting the type Library to .Net assembly failed. Type Library System_Windows_Forms was exported from a CLR assembly and cannot be re-imported as CLR assembly.'

Please suggest me is this because of some patches need to be installed or what.

Huh? Are you using Visual Basic.NET?

Yes I am!

next question is:

Are you trying out some funky COM interop thing in any area of your project i.e. VB6 does not figure ANYWHERE in what you are doing, right?

Yes when you add the reference make sure you are picking it from the .NET tab and not the COM tab.

Also, you can't add a reference to standard DLLs, only COM DLLs and .NET assemblies.

Thanks! I was actually trying to set reference from COM dll. Now tell me whats the difference since the name of the dll was same.
System.Windows.Forms.dll

One is a COM version for use in other COM compaint panguages like VB6 and the other is the native .NET assembly for use with .NET.

Ok! Thanks for info. I've jsut started to learn .NET