[Solar-OpenOffice] Undelivered Mail Returned to Sender

This is the Scanmail program at host vfmail7.u-netsurf.ne.jp. I'm sorry to have to inform you that your message could not be delivered to one or more recipients. It's attached below. For further assistance, please send mail to <postmaster> If you do so, please include this problem report. You can delete your own text from the attached returned message. The Scanmail program <[email protected]>: host maileca.u-netsurf.ne.jp[202.233.3.138] said: 553 5.3.0 <[email protected]>... User Unknown (in reply to RCPT TO command)