You can use the Enhanced-List Application (ELA) to create distribution lists for delivering messages to a large number of recipients.
Messaging supports a maximum of 1,000 ELA lists. Each ELA list can have a maximum of 1,500 members. You can nest ELA lists to create larger lists.
Before you implement ELA, obtain the following information:
An available CoS number. The default for ELA is 8. ELA uses the CoS number for list mailboxes and the shadow mailbox.
A range of extensions to use for list mailboxes. You do not need this information to set up ELA. However, you need this information to provide extensions for the list mailboxes when you begin creating lists.