Aux accounts are no longer created for a group email address when a "Google Group" will suffice. For more information visit Google Group vs Aux Account. An "Aux" account is an additional UMSID that is tied to your primary UMSID. Aux accounts are created only in specific situations where other solutions, such as a "Google Group Email" are not sufficient.
To request an Aux Account, click the Request Aux Account button to the right and complete the form that is then presented.