To Create a User List That Is a Mailing List

Right-click the User Lists node and select New > User List.

The New User List Properties dialog opens.

On the General tab:

Enter a name for the mailing list.
(Optional) Enter a description.
Set Type to This user list is a mailing list.
The mailing list is a global list by default.

Turning on This user list is a mailing list enables the Change button, which lets you change the owner of the mailing list.
(Optional) To change the owner, click Change. In the Select Owner dialog, select the owner for the mailing list and click OK. The new owner displays in the Owner section.

Click OK.

The new mailing list is added under the User Lists node.