Undelivered Mail Returned to Sender

[Mail Delivery System]

This is the mail system at host fiordland.canonical.com.

I'm sorry to have to inform you that your message could not
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For further assistance, please send mail to postmaster.

If you do so, please include this problem report. You can
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                   The mail system

<milo.casagrande@gmail.com> (expanded from <milo@ubuntu.com>): host
    gmail-smtp-in.l.google.com[173.194.78.27] said: 552-5.7.0 This message was
    blocked because its content presents a potential 552-5.7.0 security issue.
    Please visit 552-5.7.0
    http://support.google.com/mail/bin/answer.py?answer=6590 to review our 552
    5.7.0 message content and attachment content guidelines. x16si1312832wia.7
    - gsmtp (in reply to end of DATA command)
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Un messaggio incapsulato è stato rimosso...
Da:         tp@lists.linux.it
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Data:       Sat, 30 Aug 2014 12:23:42 +0800
Dimensione: 46109
URL:        <http://lists.linux.it/pipermail/tp/attachments/20140830/c7bf54b7/attachment-0001.mht>