I'm writing a desktop application in C# that must run under XP, Vista, and Windows7. Under XP the application can write to the registry and save file to an application subfolder in program files, e.g. "c:\program files\MyApp\DataFolder". When run under VIsta and Windows7 I get a popup dialog that it can't save files to the "c:\program files\MyApp\DataFolder", because of permissions, would I like to use my documents instead. Additionally code that writes to the registry under XP will not work under Vista/Windows7. What must I do to insure my app has the correct permissions to be able to perform these actions? This is a simple desktop application that the user installs using an installer built along with the project using VS2008.