1. Log in to Plesk
2. Go to Mail Accounts > email address > Forwarding tab.
3. Select the Switch on mail forwarding checkbox.
4. Specify one or several email addresses to which email must be forwarded. When specifying email addresses, separate them with white spaces, commas, semicolons, or type each of them on a new line.
5. Click OK.
If you do not want to keep copies of forwarded messages in the mailbox, go to Mail > email address, clear the Mailbox checkbox, and click OK.
To switch off mail forwarding:
1. Go to Mail Accounts > email address > Forwarding tab.
2. Clear the Switch on mail forwarding checkbox and click OK.