FBML rendering in IFrame application

My iframe application don't render facebook tags, I tried to change to connect url to localhost/po开发者_高级运维rt but it still not working, is anyone have any suggestion?

For clarification I can see some text in my application, I just can't see the facebook tags

(It's happend to my in Facebook Developer Toolkit iframe sample code)

Thanks

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I don't sure where to find the callback url, and the connect url because I didn't found them under the facebook application setting configurations- I think the set of the url connect is , this was the original setting, and I found in some forum that I need to change it to localhost/port

Could you elaborate on your settings, particularly for the connect url? You can't put "localhost" into the Facebook settings - their servers don't know who you are when you say that. To them "localhost" means that facebook server. You need to enter your external IP address, and you may also need to open port 80 to let them load your page from there too.

If your application is otherwise working, then you must have put the correct IP in the callback url, otherwise nothing would be working. Whatever the case, the callback url and connect url must be on the same domain.