Is it possible to create a mailbox or forwarding for domain alias in Plesk?
Plesk does not allow creating mailboxes under domain aliases. Instead, the mailboxes of the primary domain are used.
If on domain alias creation select the Mail service option, the mailboxes created under the primary domain will also be available under the alias.
So, the necessary forwarding rules can be configured on the mailboxes of the primary domain.
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