First log into the Plesk Panel. Then click on the name of the domain you wish to add the e-mail address to. This will load the domain’s settings page. Now click on the mail icon, followed by the Preferences tab on the following page.

To setup catch-all, select Catch to address and enter the e-mail address of the account in the field provided.Click OK.

The change is instant and all unknown e-mails will now be forwarded to the chosen account as soon as they come in.