I can create an add-in and when I run it in debug mode everything seems OK. Visual Studio opens a new instance of Visual Studio where I can see the command button for the add-in on the Tools menu, and it's all fine. But when I want to use the add-in with another project I can't see the command button even though all three check-boxes in the row for the add-in the the add-ins manager are checked. What do I have to do to actually use my add-in?