Where is this value stored?

I keep getting these entries in the log '/blog/rss/FB.Share has resulted in an error. Details: 404 Not Found' and this The link to 'http://pcwizardsrus.com/FB.Share' has resulted in an error. Details: 404 Not Found
I seems to be coming from http://pcwizardsrus.com/blog/rss/2
My question is where is this value stored? '/blog/rss/2' I searched the DB and can't find it.
Thanks
Igor