When you build an add-in project, it installs the add-in on your development computer. Even if you close that project and start another, or even close Visual Studio entirely, all add-ins you have built will still run when you start the Office application on that computer. If you're not expecting the add-in to run, you might be surprised by what you see the next time you open the application or test a new project. This video shows how to easily uninstall add-ins from your development computer after you build them if you don't want them to run any more. Basically, you run Clean Solution, which is on the Build menu. But watch the video for proof!

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Forum: Multiple add-ins running

Office Solution Build Process Overview

Duration: 2 minutes, 50 seconds