NuGet GUI Manager Button Disappears

Question

My NuGet GUI button sometimes disappears from the Tools menu. Why does this happen, and how can I fix it when it does? I have Visual Studio 2012 and I'm using Windows 8.1 in a VirtualBox-created virtual machine, in case this is a version-specific issue.

Also, is there another way to get to this window from Visual Studio besides the Tools menu?

Answer 1

The reason I wasn't seeing the option, along with several options, was because I was running the project at that point, as you can see by the orange bar at the bottom.