Fernando 96 Reputation points


I have the following problem with a WACOM STU SIGNATURE TABLET with the following message, when I compile the sample code:

An unhandled exception or type 'System.Runtime.InteropServices.COMException' occurred in DemoButtons.exe

Additional information: Fetching the COM classfactory for the component with CLSID {2000D7A5-64F7-4826-B56E-85ACC618E4D6} failed due to the following error: 80040154.

The DLL that generates the exeption is interop.wggssSTU.dll

The code (is from wacom example)

    private void button1_Click(object sender, EventArgs e)  
      wgssSTU.UsbDevices usbDevices = new wgssSTU.UsbDevices(); //error  

I tried to register via regsrv32 but get the message DLLentry not found.

This class error appears also when I compile with EMBARCADERO RAD STUDIO 10.3 with the DELPHI sample version...

Best Regards,


An object-oriented and type-safe programming language that has its roots in the C family of languages and includes support for component-oriented programming.
7,498 questions
No comments
{count} votes

Accepted answer
  1. Fernando 96 Reputation points


    I really appreciate your response to my concern.

    The solution was combined, due on the one hand to the fact that the dll, which I needed, was somehow corrupt and on the one hand I had to request the updated sdk again and on the other to modify according to his advice, the way to compile the solution:

    Project + Properties, Build tab, then I changed Platform Target to x86.

1 additional answer

Sort by: Newest
  1. Timon Yang-MSFT 9,511 Reputation points

    This problem means that your computer is missing some COM components.

    One probable reason is that the managed assembly used by your program uses 32-bit COM objects, but you are now trying to run the program in a 64-bit environment.

    You can refer to the links below. Although the missing COM components may be different for everyone, the solution should be similar.

    How to repair COMException error 80040154?

    Error 80040154 (Class not registered exception) when initializing VCProjectEngineObject (Microsoft.VisualStudio.VCProjectEngine.dll)

    Class not registered Error

    If the response is helpful, please click "Accept Answer" and upvote it.
    Note: Please follow the steps in our documentation to enable e-mail notifications if you want to receive the related email notification for this thread.