IanCP - 9:51 pm on Sep 21, 2012 (gmt 0)
Did you really type the url with a leading period
Nope. I literally put in http://example.com/
Used 301 Redirect and see your result anytime in any search engine see only one results with (www.). And add sitemap.xml and verify in webmaster tools.
That's an impossibility to do with http://example.com/ simply because it doesn't exist.
My take on this is that somewhere out there someone has place a link to http://example.com/blue-widegets.htm and that is the cause.
Similarly I've often had problems with Google and one or more dodgy links I tracked down to a blog somewhere:
http://www.example.com/green-widegets.htm[full stop or question mark]