keyplyr - 7:38 am on Dec 11, 2013 (gmt 0)
Don, I have index.html files in all my image directories and this M$ phenomena still occurs regularly. Even after I moved my main site to a new (shared) hosting company, it continues. And I have no redirects or dynamic pages.
I also get ill-formed requests for http://example.com/page-name1/page-name2.html
This happens with both msnbot and bingbot but no other SE bots. This has been going on for well over 2 years. At one point I had an ongoing email dialogue with an M$ tech. I sent him daily logs showing over 100 daily 404s from their bots, day after day. I was told they had probably gotten a corrupted index and that it should "wear off" very soon. It hasn't.