When I first installed Visual Studio, I chose to customize my environment for \"Visual C++\" development. Now, I am working primarily in C# and want to change this setting t
Tools → Import and Export Settings → Import Selected Environment Settings...
A dialog will appear, prompting you whether or not you want to save your current settings. If you've made extensive customizations and might want to go back to them at a later date, you should choose to save them.
Then click "Next". You'll be prompted to import a set of environment settings. At the top will be the default environment settings options, customized for each language. In your case, you'd choose C#.
If you wanted to re-import your saved settings, you'd do it the same way—just browse to the saved settings file in the final step of the wizard.
You could also reset all of the settings from the command line:
devenv /resetsettings
And then choose all over again when prompted.
Note: I prefer "General Developer Settings" if you are going to do development in different technology areas (C++, C#, VB, etc.).