Throttling is used when any mail server administrator would like to set the limit on a mail and bandwidth utilization of particular user.

1. Log in to SmarterMail as administrator.
2. Select desired domain.
3. Click Settings from actions toolbar and select desired Users from drop-down menu.
4. Click Edit in the actions toolbar.
5. Click the Throttling tab.
6. Set "Outgoing Messages per Hour","Outgoing Bandwidth per Hour","Bounces Received per Hour" and its respective action.
7. Click Save.

Thanks!

It is recommended to use email cleansing service before starting an email campaign.