dotCover adds its own configuration page to the Visual Studio options. This page lets you suspend or resume dotCover, that is fully unload it from Visual Studio and from the memory or reload it. If the product is not running and that is not because it has been suspended (for example, if your license has expired), there is a cue banner with explanatory text.
tip
If your license has expired and you want to enter a new license key, this page is where you should go. After clicking Resume Now, the License Information dialog will appear, and you will be able to enter the new license.