I’m taking a quick time out from getting Version 1.2 of Rubberduck ready to talk a little bit about working with COM Add-Ins and Installshield’s installer builder. (Awkward phrase, I know.) First, let me say that I’m not impressed with InstallShield LE, not even a little bit. As awkward as that phrase was, this tool is so much worse. Granted, it could be that it’s a great tool and I’ve just not tried the alternatives yet… but I doubt it. Something out there has to be better. When I find it, I’ll let you know.
I’ve digressed though. I’m here for a reason. I fight with this setting in the installer each and every time I build a new version. Enough is enough. This is my documentation. You see, I spent a few days creating a new installer. The installer would build without error and install without error, only for me to receive a
Could not load the add-in.
message upon opening the VBA IDE. It’s incredibly frustrating, but here’s how to do it right.
When creating an add-in for the VBA Editor, or any MS Office application really, you have to register the assembly for COM Interop. Most of the blogs and tutorials out there show you how to do this with Regasm or Visual Studio. That’s fine for development, but if you want any one else to ever actually use your software, you’ll probably need to create an MSI package and/or a Setup.exe. That program will need to register the assembly on the target machine.
Go to the Project Assistant, and then to the Application Files screen. You’ll need to take a couple of Actions here to properly create the installer. Obviously, you’ll need to add the Primary Output. What’s not so obvious is that you’ll also need to manually link the
*.tlb file by selecting installation folder, then the Add File button, and pointing to the file in your
The second not so obvious (and most frustrating) thing is you’ll need to set the properties on the assembly correctly. So, right click on the Primary Output, and select Properties. In the dialog, go to the COM & .Net Settings tab. Once you’re there, use the settings below.
You’ll need to do the same for the *.tlb file, only don’t check the COM Interop box this time.
Now when you build the Assembly & Installer and then install, your COM Add-in will properly load. There’s a little more to getting your installer perfectly right than that, but I’m short on time and that hidden property is what tripped me up for the last few days. So, hopefully I’ve saved some one some pain. Even if that someone is me a month from now.
Until next time, Happy Coding.