Rozesílám spamy ?

Odpověděl jsem na email,vrátilo se mi hlášení níže.Pc jsem projel SAS v nouzovém režimu,také Avast nic nehlásí,kde může být ještě příčina?
Děkuji za odpovědi.
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A message from <cosi1@volny.cz>
to: cosi2@volny.cz

was considered unsolicited bulk e-mail (UBE).

Our internal reference code for your message is 07458-20/9HZja6C+e9xa

The message carried your return address, so it was either a genuine mail
from you, or a sender address was faked and your e-mail address abused
by third party, in which case we apologize for undesired notification.

We do try to minimize backscatter for more prominent cases of UBE and
for infected mail, but for less obvious cases some balance between
losing genuine mail and sending undesired backscatter is sought,
and there can be some collateral damage on either side.

First upstream SMTP client IP address: [93.99.7.10]
According to a 'Received:' trace, the message apparently originated at:
[93.99.7.10], pentium unknown [93.99.7.10]

Return-Path: <cosi1@volny.cz>
From: "cosi" <cosi1@volny.cz>
Message-ID: <D19FCB113F1040C48F650234DD387F64@pentium>
Subject: bb

Delivery of the email was stopped!

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Return-Path: <cosi1@volny.cz>
Received: from pentium (unknown [93.99.7.10])
by smtp.sloane.cz (Postfix) with SMTP id B76D01FA213
for <cosi2@volny.cz>; Tue, 26 Oct 2010 20:58:35 +0200 (CEST)
Message-ID: <D19FCB113F1040C48F650234DD387F64@pentium>
From: "cosi" <cosi1@volny.cz>
To: "cosi2" <cosi2@volny.cz>
Subject: bb
Date: Tue, 26 Oct 2010 20:58:35 +0200
MIME-Version: 1.0
Content-Type: multipart/alternative;
boundary="----=_NextPart_000_004D_01CB7550.8E5BB78 0"
X-Priority: 3
X-MSMail-Priority: Normal
X-Mailer: Microsoft Outlook Express 6.00.2900.5931
X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2900.5994
X-Antivirus: avast! (VPS 101026-1, 26.10.2010), Outbound message
X-Antivirus-Status: Clean