I came across exactly this issue: Microsoft-HTTPAPI/2.0
And the last comment on the question from Ivan Milosavljevic contained the answer. The reason given for closing:
closed as off topic by Kev♦ Jul 21 '11 at 12:04
Questions on Stack Overflow are expected to generally relate to programming or software development in some way, within the scope defined in the faq.
I would have to disagree, I think this is on topic, it's about setting up development environments for both Microsoft tech. (Visual Studio) and PHP (Apache, WAMP).
Maybe this should be reopened—it's in my favorites for sure.