As far as I recall, System.Data.dll is part of the base class library and should indeed be installed with the .NET framework. If your server is missing it, I would recommend uninstalling and reinstalling the .NET framework. It sounds to me like there was corruption with the original installation. As far as a "Web Setup Project", it would not solve your particular issue. It will include only those files relative to your application, not those that are part of the base class library of the framework. In other words, it would also not include System.Data.dll. I've been using xcopy deployment for my ASP.NET projects since beta 2 with no issues. Though I could be wrong, this strikes me as an environmental problem rather the something you could correct with your application. Hope that helps a bit. :) --Jesse