Reference: http://community.office365.com/en-us/forums/160/p/71382/266109.aspx#266109 Using Office365, one of my users has mac outlook 2011, windows outlook 2010, and obviously OWA. She has a distribution group where she's the only member, and she has SendAs privilege (I assigned via powershell). In outlook 2010 and OWA, she specifies the From, selects the distribution list from GAL, and sends. From that point onward, it always appears in the From drop-down. On Mac Outlook 2011, the From drop-down only lets her specify another account on her computer; doesn't seem to know about any SendAs permission, doesn't seem to give her the ability to SendAs another email address from the GAL. Is there something we're missing? Or is it just not supported? We tried waiting a few days, deleting and recreating the account from Mac Outlook 2011, waiting a few more days... Still nothing.