The sender email address for a PowerMail will always default to the email address of the databank user who is currently logged in. You can change this by following these steps:
1. From the 'COMMUNICATION' dropdown choose 'PowerMail'
2. Select the 'Subject' of the PowerMail you want to edit
3. Click on 'Properties'
4. (1) Next to 'Sender Email Address' type in the email address you want the PowerMail to come from and (2) Select 'Submit'