Imagine situation you’ve just installed new shiny extension to your Visual Studio 2017 - you restart and … nothing happens VS is not starting. What to do?
There is couple of options:
Figure out what went wrong. If you start Visual Studio with /log switch you should get details log file. I’ve tried this with mixed results in the past.
Uninstall problematic extension - .vsix file is just zip archive. When you unpack it you get extension.vsixmanifest file in which you find, extension id:
<Identity Id="extension-id-1234" />
Open your Developer Command Prompt and execute:
vsixinstaller /u:extention-id-1234
That should do the trick - the next two options are rather last resort.
If you for whatever reason cannot obtain extension id, you can try to delete plugin folder. It should be located in c:\program files (x86)\Microsoft\VisualStudio[Community/Pro/Enterprise]\Common7\IDE\Extensions. The trick here is to find proper folder - all the plugin folder names are randomly generated. You have to make educated guess - files inside folder can give you some clues.
If all the above fail - you can use atomic option - reset all settings for your instance of VS. To do that navigate to %APPDATA%\Microsoft\VisualStudio\ and delete folder 15.0_??????? where question marks are some random instance characters. After that you get default VS settings and you will have to install and configure all your extensions from scratch.