How to install a local mail server or switch between mail servers in Plesk for Linux?
Plesk allows to install the following mail components and switch between them using Plesk Installer:
Note: Changing SMTP server does not affect mailboxes, but changing IMAP server may affect mailboxes. Visit this KB article to learn more about potential issues.
Instructions for Plesk on Windows Server are available in this KB article.
To configure external SMTP server in Plesk, visit this KB article.