I'll go with this one.
http://msdn.microsoft.com/en-us/library/ms229002.aspx because it's the one Microsoft follows for the .NET Framework and the one FXCop is based on. And while it says "Framework" in the title, there is good stuff in there for app devs. Or, you can read the boiled down version at
http://idesign.net/idesign/DesktopDefault.aspx (Coding standards link on the right)
>
>But which one is the grail - you know - THE bible of best practices? There must be one, right? If they truly are BEST PRACTICES.
Craig Berntson
MCSD, Microsoft .Net MVP, Grape City Community Influencer