Question forward mails get no error

[Oli_mt]

Hi,

I have a problem with forward mails.

Following example.

Email: [email protected] (My adress in plesk)
Email: [email protected] (the forward adress insert in [email protected])
Email: [email protected] (sender adress)

If I send a mail from [email protected] to [email protected]
Every thing is fine and [email protected] get the mail

But now if i change the adress [email protected] to [email protected] (no existing adresse)
and i send mail to [email protected] the sender [email protected] get no error mail
like

Mail delivery failed: returning message to sender
This message was created automatically by mail delivery software.

A message that you sent could not be delivered to one or more of its recipients. This is a permanent error. The following address(es) failed:

[email protected]
host mail.plesktest.abc [xxx.xxx.xxx.xxx]
SMTP error from remote mail server after RCPT TO:<[email protected]>:
550 5.1.1 <[email protected]>: Recipient address rejected:
User unknown in virtual mailbox table


Please can you help me ?!

Regards
Oliver

Plesk Version 17.5.3 Update #43