Where to get icm.div3 file

Hi,
When I try to play a downloaded video, I get a message that what is needed to play the video is
“icm.div3”. I’ve searched all over the web on this and can not find the answer.
When I do try to play the video it says it is going to the website to get this file but then say’s it is unable to find it whether it is Windows media player(8.0) or real player. Any help would be appreciated.