I work on a project that implements a RESTful webAPI that allows users to interact with the system over HTTP to get data and update things...nothing special.
When getting my environment set up, I had a problem sending the API POSTs and DELETEs. I would always be returned a 405. Well, the short of it came down to the WebDAV module that IIS 7 had running. I uninstalled that and it worked like a charm; my requests are now going through successfully.
This is the article that helped me out.
Total wtf?? moment.