I am using 2.5.5 and cannot embed a youtube or vimeo video on the Message Froum, Classifieds, Event Calendar. I can use the embed code in a block but not in any of the modules.

I can post video using the youtube icon on the editor but I want to post the embed code which uses iframe

I am trying to embed a video below and it does not work!

<iframe width="640" height="360" src="http://www.youtube.com/embed/6YD8Lt7avdU?rel=0" frameborder="0" allowfullscreen></iframe>

I think you should use this:

I too have a similar problem. Using dhtml the youtube button doesn't give the video. Using tinymce I, as a webmaster, can use <iframe>. However, members can not. It gives the message "iframe filtered". So I suppose it's a permission thing. But how and where can I set that?