How do I detect what .NET Framework versions and service packs are installed?

Question

A similar question was asked here, but it was specific to .NET 3.5. Specifically, I\'m looking for the following:

1. What is the correct way to determine which .N

Answer 1

There is an official Microsoft answer to this question at the following knowledge base article:

Article ID: 318785 - Last Review: November 7, 2008 - Revision: 20.1 How to determine which versions of the .NET Framework are installed and whether service packs have been applied

Unfortunately, it doesn't appear to work, because the mscorlib.dll version in the 2.0 directory has a 2.0 version, and there is no mscorlib.dll version in either the 3.0 or 3.5 directories even though 3.5 SP1 is installed ... why would the official Microsoft answer be so misinformed?