Using TLBIMP.exe

This is related to the question i asked here:
https://www.experts-exchange.com/questions/23105218/This-encryption-method-works-in-ASp-Net-VB-Net.html

So, I downloaded VBCorLib.dll  from sourceforge. I couldnt add a reference to it in my ASP.Net app.

I tried using tlpimp from here:http://msdn2.microsoft.com/en-us/library/tt0cf3sx(VS.80).aspx

When I do this: tlbimp VBCorLib.dll /out:enctest.dll

*** I get this error:
TlbImp : warning TI0000 : Type library importer has encountered an interface not
 derived from IUnknown: '_HiddenInterface'.
TlbImp : error TI0000 : System.SystemException - The type library importer encou
ntered an error during type verification. Try importing without class members. :
 System.MissingMethodException - Method not found: 'System.Collections.IEnumerat
or enctest._ICollection.GetEnumerator()'.

What am I doing wrong??