I'm pretty sure ResearchSoft, maker of EndNote, has gone on record to say that EndNote 6 will not be updated for Word 2004. No specifics yet given for EndNote 7 other than to say it doesn't work.
This is the current statement on their website: "We plan to release a version of EndNote that is compatible with Office 2004 for Mac OSX."
Not sure if that means waiting until EndNote 8 or what.
In the meantime, there are a couple of work-arounds.
1) Put citations in manually, save as an RTF file and scan the document from EndNote.
2) Keep Word v.X installed. As long as you don't try to run both Word 2004 and Word v.X at the same time, Word v.X plus the EndNote plug-ins will continue to work.
3) Switch to BookEnds (
http://www.sonnysoftware.com/). Not an option for me - too much invested into EndNote in terms of old documents, libraries, formatting styles and not to mention all the reference libraries used by my associates.
However, I encourage people to send a customer service letter to Microsoft voicing your displeasure that they altered the plug-in module format enough to break the EndNote modules. ResearchSoft is at the mercy of Microsoft when it comes to EndNote's ability to work from within Word.