When I add a new setting in the Settings.setting file using the designer, rebuild the project, and then attempt to reference it in code as in "Settings.Default", intellisense doesn't show the new property and R# flags the line as an error. The app compiles fine. I am not sure if this is a Visual Studio problem or R#. The only way I know to get rid of this issue is to restart VS.
I am using VS 2008 SP1.