Is it possible to add an external guest member to an office 365 group from the outlook 2019 client , NOT the outlook web interface ?
We can add external members to groups from OWA , not when we try via outlook 2019 we get a message about this operation being prohibited due to organizational policy. As the admin I haven’t found any explicit setting to block guess group additions from only the outlook client, since we can add them via owa. Is this just a bad error message and it is impossible to add external group members via outlook , or is there some outlook client specific setting to allow this . No one in our organization uses owa, so it is cumbersome to have to connect to owa just for this purpose.
Yes, it's possible, but it might also depend on the Outlook version you are using. Keep in mind that most Office 365 related features are only available within the Outlook client that comes as part of the click-to-run Office install, not the standalone Outlook SKU nor the "perpetual" version.