That means that you've set some sort of restriction on your Facebook Application. Please go to the Facebook Developer area and try removing the restriction (age, geographic region, etc) and see if that helps.We could not log you in: You can't log in to this app because you do not meet this app's requirements for country, age or other criteria.
Does it still just show the authentication popup and then disappear? Can you try logging out of Facebook.com and then clicking the button on your site. Does it ask for your credentials and then just disappear then too?I have noticed that is only my account that can't access our site via facebook.
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