Yesterday I spent an embarrassing amount of time trying to figure out why my Visual Studio extension’s Options Page no-longer updated or could be read. It was tested and working and after I made a few changes and tested again, I couldn’t read any of my extension’s properties in the Visual Studio options dialog. I even removed my options page entirely and it somehow still existed in the visual studio options. Well here was the culprit. I viewed the .csproj for my project and found
<GeneratePkgDefFile>false</GeneratePkgDefFile>
Not only does your extension must be a VsPackage (not just a basic vsix) but GeneragePkgDefFile needs to be set to true.