A Vyopta username is formed as userpart@domain - where the domain is the organisation to which you belong.
This is normally the email address of the user - an assumption that is made in the automatic sign up procedure.
This assumption can base problems when, for instance, you wish to have users who have a different email domain - perhaps a 3rd party assisting you, or a contractor's sub domain.
Such users should not attempt to use the automatic sign up facility, but, instead, an administrative user of domain.com should manually add these users in the form of
Once added, a list of users with the correct email addresses, should be supplied to Vyopta Support in a helpdesk ticket. Vyopta Support can ensure that the users' email addresses are corrected.