I actually found this download via ActiveWin. Here's the scoop: The download "repairs access to .NET Framework Reference help content in Visual Studio 2005 Express Edition Beta 2."
Visual Studio 2005 Express Edition Beta 2 Help Fix
The Beta 2 Visual Studio 2005 Express Editions shipped with an issue that prevented the majority of the .NET Framework API reference documentation from appearing in the Table of Contents, Index, and Search Results windows for either Online or Local content. The source of the problem is faulty "filter" definitions. These issues have been fixed in later builds of the Visual Studio 2005 Express Editions.