When we publish the InfoPath form to SharePoint. I thought that I had tried everything. I had tried publishing to a document library, as a content type, trying to modify content types, etc. I got a variety of error messages including “Updating the site content type failed”. Actually it updated the document template but I wasn’t thinking about that when I saw the error message.
What I realized when I dug into the issue is that InfoPath 2007 couldn’t modify the content type because it had been created at the site collection level – not the subsite level that I was doing my testing from. You can only modify a content type from where it was created. When I backed up in the wizard and I gave it the URL for the site collection root rather than the sub-site and then rolled forward through the wizard again it worked.
So if you’re having trouble getting InfoPath 2007 to publish to SharePoint … try publishing to the root of the site collection. (I still have other issues this didn’t fix like the fact that a properly derived form isn’t showing up as one to modify – but one problem down.)