Installing the same-name addin programatically

[crewaustin66]

Requirement:
We have versions of the same file named like:
Product 171115.xla
Product 171110.xla

Each of these contains a project called "Product" and must be loaded from "Product.xla"
What I need to do is copy the first version of the file to "Product.xla" and attach the add-in and then do the same process with the next version.

Problem:
For some reason, Excel gets stuck on on the first version no matter what I try. The "Product" project is successfully removed, a version of the file is copied to "Project.xla", then the add-in is attached. The "Product" project is once again visible. What I'm seeing is that, even though I uninstalled the currently loaded "Project.xla" and loaded a newer "Project.xla", Excel remembers the first version no matter what.

IF I change the name from "Product.xla" to "Product2.xla" before I attach it, this works. The problem here is that the "Product" project expects to be running under "Product.xla" and fails under "Product2.xla". I can get the old "Product.xla" unloaded fine. I can get the new version of "Project.xla" to load. When I do this, why do I see the original "Project.xla"? I hope this all makes sense.

Thanks,
Crew