By default MDaemon 11 requires users to login to their mailboxes via POP3, IMAP, Outlook Connector and WorldClient using their full email address as their username and this requirement will be on by default on both existing installations that upgrade to MDaemon 11 and brand new installations.
To turn this requirement off choose Setup -> Preferences -> System in the MDaemon Interface and untick the highlighted option below then apply the change:
