We're exchange 2007, with a mix of Outlook 2003, 2007 and 2010. I have some users (on Outlook 2007), that are reporting when they reply all to some messages, a distribution group is getting mysteriously added to the TO: field. The group that gets added just happens to be the first item in our global address list, it is a distribution group that begins with _DL_.
Anyone have any clues as to what may be the cause here?