SCRIPT5007: Unable to get value of the property 'SetReturnValue': object is null or undefined

See http://msdn.microsoft.com/en-us/library/gg622942%28v=VS.85%29.aspx

Basically, IE9 breaks flash ExternalInterface calls if your flash component is embedded with an object tag with an embed tag fallback, and the object id and embed name is the same.

The easiest workaround is to tell ie9 to render your page in IE8 Standards mode.To do this, insert this in the element:

<!-- Enable IE8 Standards mode --><meta http-equiv="X-UA-Compatible" content="IE=8" >

Otherwise, you might just want to use the object tag only or embed tag only.

Much of the time, this can be caused because of an embedded object swf video player (for example: JW Player etc.)

Internet Explorer seems to require two attributes for the OBJECT tag, namely classid AND id

For a SWF player use:

classid="clsid:d27cdb6e-ae6d-11cf-96b8-444553540000"id="dummy"

NB - in principle, id can be any (non-taken) dummy string

Other good sources on how to embed video:

http://www.w3schools.com/html/html_object.asp

http://www.2webvideo.com/blog/embed-swf-flv-mp4-videos-in-webpage

Make sure you specify the id tag (it must have the same value as the name tag).Although Adobe writes that id is an optional tag, Internet Explorer needs the id to address the swf object with the javascript-flash interface.