Sorry, I can't follow you.
Open Other User's Mailbox is sometimes greyed out, but then I should use Use Open Other User's Mailbox.
How can I access Use Open Other User's Mailbox, if it is greyed out?
I came accross a wiki page "Enable Sharing Addin":
EnableSharingAddin - Zimbra :: Wiki. Is that still right for Outlook Connector 5 with Outlook 2003? If so, I have a problem: There is neither a sharing tab in the folder properties setting, nor a registry entry like HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Office\Outlo ok\Addins\SharingAddin.Addin