Rick, the only thing that I can think of would be to do the conversion in two steps. Convert it first to e.g. version 2008, and then version 2011. I don't think the current 2011 goes as far back as 2004. I've heard people being unable to convert 2006 and
older. The following thread may have some more information on this topic:
Microsoft Streets & Trips 2011 unable to open a map saved in much earlier version
Laptop GPS World