Testing with " http://www.youtube.com/watch?v=GxzRfW3gMJA"

Below is using full path in the youtube tags

http://www.youtube.com/v/GxzRfW3gMJA

Below is just using video id in the tags

https://www.youtube.com/watch?v=GxzRfW3gMJA

EDIT: Supposedly, it's supposed to work with the latter, as stated by search in Google in its infinite wisdom it depends on how the custom BB code is setup. I haven't done a youtube embed in a phpbb ever, so I wouldn't know. *runs off to try it in a Virtual Machine with phpbb3 on it*

EDIT2: Silly me, I thought it was an option in phpBB3 by default, turns out you had to add it in the admin control panel. Anyway, I got it working on my personal test bed with these set of instructions

EDIT THE THRID: HTML used here fetched from the page source.

<embed src=""http://www.youtube.com/watch?v=GxzRfW3gMJA"" type="application/x-shockwave-flash" allowscriptaccess="always" allowfullscreen="true" width="480" height="390"></embed>

Code that I used in my testbed fetched from the page source (sans the line the link had containing a link that they have below every video directing them to their website to teach others how to do the same, just a link, text, and line break codes anyway...even I know that much)

<object width="425" height="350"><param name="movie" value="http://www.youtube.com/v/GxzRfW3gMJA&hl=en_US&fs=1&"></param><param name="allowFullScreen" value="true"></param><param name="allowscriptaccess" value="always"></param><embed src=""http://www.youtube.com/v/GxzRfW3gMJA&hl=en_US&fs=1&"" type="application/x-shockwave-flash" allowscriptaccess="always" allowfullscreen="true" width="425" height="350"></embed></object>

...however, I don't really know how 'embed' and 'object' work that well to immediately point out whats wrong. I hope this information will be of help in resolving this.. 😉