I have this anyoing error since I installed Facebook comments. I'm getting this yellow warning box under the comments field.
It's not under all posts and sometimes it disapears after a while. See: http://cust2.factory42.nl/blog and the fb debug: https://developers.facebook.com/tools/debug/og/object?q=http%3A%2F%2Fcust2.factory42.nl%2Ftrouwreportage%2Fontspannen-trouwreportage-in-dordrecht-rotterdam%2F
It gives a 404 response. I checked the app domain (cust2.factory42.nl) and website url (http://cust2.factory42.nl/) and it seems to be correct.
Please can anybody help?