Hi,

I created an automation in .NET. When I leave all the code in one namespace everything goes well.

Recently I decided to refactor the project and put my interfaces in a general library (just a class library). I reference this library in the other libraries that use the interfaces.
The methods are still exposed etc, but when I try to instantiate (in excell (macro), or in other applications that allow the automation to be used), it throws an exception, saying that the com object can't instantiate.

The assemblies are strongnamed, classes used have a default constructor w/o parameters.

Steven Gilissen

Just found the solution to my problem. Rather stupid how I had to find it but hey, I learned my lesson now.

I had 2 class libraries. One of them holding the interfaces (general) & one just the classes whom are exposed (project1 for ref). When I made a setup project, I added the project output of project1, knowing that since the general project is referenced in project1, it would be copied. That's about right, but what it doesn't do is install the general dll in the GAC. I needed to effectively add the general assembly to the GAC folder of my setup.

I didn't realize earlier because I used GACUTIL/REGASM on the general dll and tried the com calls w/o rebooten my third party application (here: Excel). That was needed.