Unable to send message from domain where mail hosted on Google: 550 Requested action not taken: mailbox unavailable or not local

Symptoms

• One of the following bounce messages is received while sending a mail message to jdoe@example.com on the Plesk server:

  CONFIG_TEXT: Delivery to the following recipient failed permanently:
  john.doe@example.com
  Technical details of permanent failure:
  Google tried to deliver your message, but it was rejected by the server for the recipient domain example.com by mail.example.com [203.0.113.2].

  ---

  CONFIG_TEXT: An error occurred while sending mail.
  550 Requested action not taken: mailbox unavailable or not local
  Please check the message recipient john.doe@example.com and try again.

• Mail for this Plesk domain is hosted on Google Services

Cause

Mail domain is present in MailEnable configuration.

Resolution

Disable mail service for the affected domain in Domains > example.com > Mail Settings so that MailEnable configuration is not present and outgoing emails are sent via external server, or apply an alternative solution: 

1. Connect to the server via RDP

2. Open MailEnable at Start > MailEnable

3. Navigate to Messaging Manager > Post Offices > example.com > Domains:

   

4. Double click on example.com to open Properties window:

   

5. Tick the Act as Smart Host option and add either the IP address or the domain name of the mail server where email has to be redirected to:

   

6. Download the following tool from MailEnable: MERoute

7. Unpack the archive and execute MERoute.exe:

   

8. In the new window select example.com and click on the OK button to save the change: