Exchange 2013 to 2019, OWA 2019 mailboxes, 401 Unauthorized
Basically after moving a mailbox from 2013 to 2019 OWA and activesync authentication seem to fail with 401, when accessing via the 2013 URL.
Basically after moving a mailbox from 2013 to 2019 OWA and activesync authentication seem to fail with 401, when accessing via the 2013 URL.