Mailbox Provider Weighting settings for a parent account are not inherited by child accounts. If you want Mailbox Provider Weighting applied for a child account, then you will have to set it up separately. 

Prerequisite

• You need to be logged into the parent account and have administrative access.

Steps

1. Select the child account you wish to use from the drop-down menu in the upper-right hand corner of the page. 
2. Determine your weighting for the mailbox providers. 
3. Enter the weights you calculated into the text boxes. 
4. Select Update List to save changes. You can update these weights as often as needed. 
5. Go to the Campaign Overview page and select Apply Mailbox Provider Weighting checkbox.