I posted this on LinkedIn to see if anyone could help. Here's what I got so far :
I believe this has to do with what program is configured as default for the MIME type in question (application/rss+xml) or the extension (.RSS). The setting is specific to the user/machine which would explain why different users see different behaviour.
Hope this helps! :-)
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From an initial launch of Outlook, I received the following message (which appears to support Bruno's comment).
Outlook, Windows Internet Explorer, and other applications save lists of RSS Feeds that you subscribe to. The Common Feed List in Microsoft Windows maintains one synchronized list of RSS Feeds. Do you want your RSS Feeds in Outlook to be synchronized with the Common Feed List?
I'm not sure where to find the Common Feed List or where in Outlook to force that sync. I did see that in each Outlook 2007 client you can define which feeds need to appear (Account Settings > RSS Feeds) - perhaps its a matter of copying the feed source from another application into this area of Outlook. Good luck!
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Bruno, I have no idea what that means. (Darn, I feel dumb! Hehehe) How and where do I change that?
Michelle, I looked in the Account settings, but I just see the feeds I am subscribed to. I don't know if I want the common feeds list synchronised. Which one is the deciding factor? The feeds in Outlook are the correct ones. The feeds in IE are the wrong ones. I don't want to synchronise and end up removing all the feeds in Outlook.
I want Outlook to be the one point of truth for all feeds. Not any other feeds list.
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It is simpler than it sounds :-) Your computer knows how to handle different files based on the extension (.RSS), content type (application/rss+xml - this would be specified in the header of the file, not visible to the end users) or protocol (e.g. http://). The way you change it depends on the operating system you are using. In Windows 7 for example, you can go to Start > Default Programs > Associate a file type or protocol with a program.
Hope this helps! :-) Any questions, just ask.