Problem with video within Engage when uploaded to the Web

I am having an issue with an embedded video not playing once it has been uploaded to the web. (gear keeps spinnning, the video does not ever looad) It plays fine from the html file from my laptop. But the same files uploaded to the web will not play the video, although all other elements of the engage project work just fine.I did use the Articulate video encoder to convert the video to flash before embedding it into Engage. I thought it might be a video file size limitation, but I have the same issue with a very small video file - under 2 MB. I work in a school system with AD logins and group policies applied, in case that would make a diffrence. We use IE 9 and 10, and I also checked Firefox to no avail. I have looked at the tutorials on Engage and used all of the recommended settings, so I am at a loss. Any help is much appreciated!

Paula