can't create user output file

Dear,
on some domains happen that are impossible receive email.
When somebody try to send its an email receive the follow aswer (servername.it and name_domain.it are not real name):
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This is the Postfix program at host servername.it.

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

If you do so, please include this problem report. You can delete your own text from the attached returned message.

The Postfix program

(expanded from
): can't create user output file. Command output:
procmail: Renaming bogus mailbox "/var/mail/p.romani.name_domain" info
"/var/mail/BOGUS.p.romani.name_domain.NGoB"
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This is the attached file datail.txt
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Reporting-MTA: dns; servername.it
X-Postfix-Queue-ID: B5B41709B7
X-Postfix-Sender: rfc822; p.romani@dgk.it
Arrival-Date: Fri, 14 Mar 2008 13:48:30 +0100 (CET)

Final-Recipient: rfc822; p.romani.name_domain@servername.it
Original-Recipient: rfc822; p.romani@name_domain.it
Action: failed
Status: 5.0.0
Diagnostic-Code: X-Postfix; can't create user output file. Command output:
procmail: Renaming bogus mailbox "/var/mail/p.romani.name_domain" info
"/var/mail/BOGUS.p.romani.name_domain.NGoB"

Status: 
Closed (fixed)