Facebook Like Boxes returning 500 Internal Server Error

Question

Since a few days I have seen several of my clients websites, our business website and even my own personal website starting to show blank space where the Facebook Like Box iframe used to be.

Here's an example of the Facebook iframe code I'm using:

<iframe src="http://www.facebook.com/plugins/likebox.php?id=140736345955440&width=296&connections=15&stream=no&header=no&height=325" scrolling="no" frameborder="0" style="margin:-1px 0 0 -1px;border:none; overflow:hidden; width:296px; height:325px;" allowtransparency="true"></iframe>

This code worked before but suddenly the iframe URL returns a 500 Internal Server Error from Facebook. Why is the iframe breaking and reporting 500 error?

Answer 1

I experimented a little, and the reason for the 500 Internal Server Error seems to be that the ampersands (&) in the URL has to be URL escaped into &. This is new behaviour from Facebook, and honestly seems like a bug.

Answer 2

Looking further into this, it seems more likely to be that Facebook now requires that Like Boxes include the "new" URL parameter href, that points to the website's Facebook Page. Previously, the Facebook Page ID was sufficient.