Exchange 2010 SP3 RU25. Outlook 2016 (and 2007 as test). Public Folder searches for "attachment contains" returns no matches when there are matches. All other searchability in Public Folders seems OK. I can search "attachment yes or no" and it works. But if I try to search for the attachment file name or the attachment file contents, I get no results. Cached or non-cached mode makes no difference.
Anyone have any ideas?