having the same issue! please help
was working, then added some pics via simple image gallery and now not working...but have both working on another page in site...
I was all set to launch a new site this week that I spent months developing, and I also found that ALLVideos 2.4 Plugin had serious issues with IE 7 and I got errors when my IE 6 and 7 users tried to open a page with a Youtube video being displayed by AllVideos 2.4 plugin.
I FOUND A SOLUTION TO RESOLVE THIS ISSUE FOR THE TWO ROCKETTHEME TEMPLATES RT_VORTEX and SPORTICUS v 2.0 AS THEY BOTH USE JS.SLIMBOX.JS CODE AND IT CONFLICTS WITH ALLVIDEOS PLUG-IN and IE 7
Here is the solution: 
If you are using a template with slimbox code in it, then there will most likely be a conflict which causes this error in IE 7 if you are using the AllVideos plugin.
To fix this issue do the following:1.
What template are you using? If you are using a RockeTheme template such as RT-VORTEX or Sporticus v2.0, or any template from any other template provider that uses js.slimbox.js code (Slimbox) in the templates you have to find the line in the template index.php and remove the line with the slimbox code.
Here is the solution that I used to cure this issue for RT-VORTEX and SPORTICUS v 2.0:
1. I opened my template index.php file: /templates/rt_sporticus_news/index.php
I did a search for this line:<script type="text/javascript" src="<?php echo $mosConfig_live_site;?>/templates/<?php echo $mainframe->getTemplate(); ?>/js/slimbox.js"></script>
I removed the above line from the index.php file that had the js.slimbox.js code in it, as I am not using the slimbox feature at all. And even if I did use slimbox, playing the videos in both browsers correctly is more important to me and my members and visitors than anything that I could possibly think of that needs slimbox on my sites.
2. Click Save. THE ISSUE WILL NOW BE FIXED.
Go to Internet Explorer 7, and open the site and find a page with an AllVideos Youtube video embedded in the article or page and it should open and play without the error. I tried my sites and made sure on a number of pages and it appears to have cured the problem.
If you need more information for those people using RocketTheme templates go to this thread:http://www.rockettheme.com/option,com_smf/Itemid,190/topic,6655.0/This is the discussion thread that helped me resolve this major problem, which now seems so trivial, as I decided to get proactive and did not want to have to rely on Fotis to find the solution. I feel that his time is probably best spent creating cool extensions and not trying to resolve every possible template issue.
I have found that MOST cases of issues with plug-ins can be resolved by getting proactive and going to the template makers Forum site and do a thorough check to see if anyone else has had the same issue with a plug-in or extension and a specific template, and then usually someone has found a solution and has posted the fix. Also, I check the joomla.org forums to see if the same answers are there.
I am certain that there are some people that are using Joomlart.com templates and having the same issues, and if so, they will probably find the same issue of slimbox code conflicts exists in some of their templates and the solution for those templates is on their site forum, as I do know a number of templates from JoomlArt.com use slimbox code in them.
Hope this helps resolve this IE 7 error issue for everyone with this problem, because Allvideos plug-in is a great solution for most every type of video display needs.
RandyMac
West Kootenay UNPLUGGED
http://www.westkootenayunplugged.comRandyMac