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Resolved 5.1.1 recipient address rejected user unknown in virtual mailbox table

Tobias Masiak

New Pleskian
Dear all,

since this morning I cannot sent E-Mails anymore which are configured on my server using Plesk Onyx.

Thunderbird shows the error message "5.1.1 <[email protected]> recipient address rejected user unknown in virtual mailbox table".
I activated and deactivated the website and mail accounts already, checked for updates and restarted the server. Nothing changed. How can I fix this problem?

Best regards
Tobias
 
Is the recipient's domain hosted on the same server as the sender's domain? Is the MX record of the recipient's domain pointing to that same server or is it using an external service?
 
Is the recipient's domain hosted on the same server as the sender's domain? Is the MX record of the recipient's domain pointing to that same server or is it using an external service?
The recipients E-Mail is not hosted on the same server, but the website with the same domain of the recipient is also hosted on the same sever.
The senders website and E-Mail accounts are hosted on the same sever. The A & AAAA record (ipv4 and ipv6) show to the servers IP and they are entered into the plesk configuration. A special MR record is not set. Where do I have to set it in plesk and how do I determine the MX record address?
 
If the recipient website is hosted on the same server, the host thinks that is must deliver the mail locally, because the domain exists in the mail servers local-host-names list. If the mailbox of the recipient does not exist on the local server, mail cannot be delivered, for that reason you are getting the error message.

If the recipient's mail service is hosted externally, the recipient will have an alternative mail address with the external mail hosting provider, for example [email protected]. The workaround in this case is easy:
- In the recipient's account create all e-mail addresses that are available in the external mail provider account.
- Do not create mailboxes for theses addresses, but forward all incoming mail to the alternative external mail address.
 
If the recipient website is hosted on the same server, the host thinks that is must deliver the mail locally, because the domain exists in the mail servers local-host-names list. If the mailbox of the recipient does not exist on the local server, mail cannot be delivered, for that reason you are getting the error message.

If the recipient's mail service is hosted externally, the recipient will have an alternative mail address with the external mail hosting provider, for example [email protected]. The workaround in this case is easy:
- In the recipient's account create all e-mail addresses that are available in the external mail provider account.
- Do not create mailboxes for theses addresses, but forward all incoming mail to the alternative external mail address.
Great, Thanks for your help. :)
 
Hi, I have the same problem.
Sites hosted on server with domain1.com and domain2.com.
Also mail hosted on the same server for domain1.com, but for domain2.com we are using external provider.

I don't know alternate address, and we have a bunch of mailboxes for domain2.com
Is there any setup in config, to avoid forwarders?
 
The best solution for this issue when the recipient domain is hosted on the same server but the email is hosted at Google for example is to follow the guide in the link provided by @campsjos
I've just done the config for Linux in Plesk and now I can send emails to a recipient that has the domain hosted on the same VPS with the domain that's sending the email.

Check this link
Mail to external mail service is delivered locally
 
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