Registering .NET Class Library DLL with VB6 App RRS feed

  • Question

  • User-425568894 posted

    To be short and to the point, I've built a C# class library that is both COM-Visible and Registered for COM Interop. I've compiled the library, which resulted in the generation of .dll and .tlb files.

    I have another machine that's running a VB6 application. So, I copied the .dll and .tlb files over to C:/Windows/system32 folder on the machine. I then registered those files using the following:

    C:\Windows\Microsoft.NET\Framework\v2.0.50727\RegAsm C:\Windows\system32\TestClass.dll /tlb:TestClass.tlb 

    After the files were registered successfully, I added a project reference to the Test.tlb file from inside my VB6 app, then I tried to invoke a method in my new referenced class like so:

    Dim myObject As TestNamespace.TestClass 
    Set myObject = New TestNamespace.TestClass 
    MsgBox (myObject.TestMethod()) 

    It doesn't work, and I receive a -2147024894 Automation Error.

    I've read that I shouldn't install the dll into a private folder like system32. I should either be registering in the GAC or I should be registering in another location using the "/codebase" option:

    C:\Windows\Microsoft.NET\Framework\v2.0.50727\RegAsm C:\TestClass.dll /tlb:TestClass.tlb /codebase 

    Is there any reason I shouldn't be using system32? Past devs that have worked on this project have placed assembly files used by this VB6 project into system32 and there haven't seemed to be any issues.

    When I register my dll in the system32 location, I get the Automation Error. When I register my dll in another location (i.e. C:/), the method call into my class library from VB6 works as expected. What gives?

    I should mention that we will NOT be using the GAC to register any DLL's. That's just the way it is.

    Any help is appreciated.


    Wednesday, May 26, 2010 12:21 PM


  • User-425568894 posted

    I'm working on a Virtual Machine, which could be the issue here.  The obejct can successfully be registered in system32 on any other box.  I'm closing this issue. 

    • Marked as answer by Anonymous Thursday, October 7, 2021 12:00 AM
    Sunday, June 6, 2010 11:11 PM