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Mail/Domain config issues - User Unknown in virtual mailbox

GoncaloP

New Pleskian
Right, currently I'm running into an issue trying to email a client who has their website hosted on our Plesk VPS. I've looked at various threads and sites found through Google on the issue, but none of what I've read accurately resolves the situation I'm in, at least not without a huge and massive potential pain and disruption.

Basically, currently on our VPS, we have domains hosted with mailboxes (including our own), and one being hosted without (the DNS just points the main A record to server, not transfer the nameservers over). But because of the domain not having local mailboxes, trying to send emails to the clients on that domain fails to work from our own emails hosted on the VPS. So the result is the following error (actual email/domain disguised):

An error occurred while sending mail. The mail server responded: 5.1.1 <[email protected]>: Recipient address rejected: User unknown in virtual mailbox table. Please check the message recipient [email protected] and try again.

Is there a way to resolve this issue without disabling local mail on the VPS? Can't I just disable that specific domain from having a local email service? Why doesn't it just resolve from the DNS instead of this funny business?
 
Yes, all you need to do is disable mail for that particular domain rather than globally.

(when a domain exists and email is turned on for that domain, messsages are always delivered locally - no DNS lookups happen)

Open the domain's Control Panel, click on Mail tab, click on Settings, remove the tick from the box that mentions "activate mail for domain" or something similar. Unfortunately I'm in front of a Plesk 10 installation not 11, so the wording may be different.
 
Yes, all you need to do is disable mail for that particular domain rather than globally.

(when a domain exists and email is turned on for that domain, messsages are always delivered locally - no DNS lookups happen)

Open the domain's Control Panel, click on Mail tab, click on Settings, remove the tick from the box that mentions "activate mail for domain" or something similar. Unfortunately I'm in front of a Plesk 10 installation not 11, so the wording may be different.
Right, my concern is that the sites are hosted within the same webspace, and that option doesn't show for specific domains within that webspace. It is just a single tickbox. I don't want to untick that if it disables the mail service for the webspace, and it is going to be an additional expense to have to get another IP address to set up a separate webspace.
 
OK. I understand.

What you need to do is move the domain that needs email disabled into its own subscription.
Multiple subscriptions can share the same IP, with that IP being exclusive to the customer, so you won't need an additional IP.

The caveat here is that we always give each domain its own subscription, so I've never dealt with having more than one domain within a subscription and I'm therefore talking in theory rather than practice. Nevertheless I don't see a problem. I hope!
 
Hi. I've got this error but it's not quite the same situation, I think. I'm sending via a separate email to an email address on my server. I get the same error. The mail server responded: 5.1.1 <[email protected]>: Recipient address rejected: User unknown in virtual mailbox table. Please check the message recipient [email protected] and try again.

However if I send from the same email to a different email address that's not on any of the Webmail Emails I have on my server, then I don't have a problem. Can you explain please? Thanks
 
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