Unknown User Error Message, Do I have a Virus?

Question

Today I checked my AOL email and had over 40 messages in my inbox all within a very short time frame. I recognize most of the email addresses that came back with the Unknown User messages. I did not send any emails out and there is no record in my sent box that says that I send those emails. Could I have a Virus? I always thought mac computers don't get viruses. I am concern that I have one and if I do what should I do. I did change my password to my email after it happen. Here is a copy of one of the email error messages that I got. For the protection of my friends email and mine I changed it in this copy of the email. Friends email- [email protected], My email- [email protected]. I also got one additional email that was sent to me, from me that I never sent. Again no email in my sent box and of course I did not click on the link that was in that email. I will also post that email but will change only my email. Please do not click on the link since I am thinking it might be a virus but I wanted to include it, hoping it will help. Thank you in advance for your help.
ERROR MESSAGE:
* ATTENTION *
Your e-mail is being returned to you because there was a problem with its
delivery. The address which was undeliverable is listed in the section
labeled: "----- The following addresses had permanent fatal errors -----".
The reason your mail is being returned to you is listed in the section
labeled: "----- Transcript of Session Follows -----".
The line beginning with "<<<" describes the specific reason your e-mail could
not be delivered. The next line contains a second error message which is a
general translation for other e-mail servers.
Please direct further questions regarding this message to the e-mail
administrator or Postmaster at that destination.
--AOL Postmaster
----- The following addresses had permanent fatal errors -----
<[email protected]>
(reason: 550 5.0.0 <[email protected]>... User unknown)
----- Transcript of session follows -----
... while talking to mx1.webexone.com.:
DATA
<<< 550 5.0.0 <[email protected]>... User unknown
550 5.1.1 <[email protected]>... User unknown
<<< 503 5.0.0 Need RCPT (recipient)
Final-Recipient: RFC822; [email protected]
Action: failed
Status: 5.0.0
Remote-MTA: DNS; mx1.webexone.com
Diagnostic-Code: SMTP; 550 5.0.0 <[email protected]>... User unknown
Last-Attempt-Date: Thu, 7 Oct 2010 18:27:52 -0400
Return-Path: <[email protected]>
Received: from imo-ma04.mx.aol.com (imo-ma04.mx.aol.com [64.12.78.139])
by imr-da06.mx.aol.com (8.14.1/8.14.1) with ESMTP id o97MRjkm008439
for <[email protected]>; Thu, 7 Oct 2010 18:27:45 -0400
Received: from [email protected]
by imo-ma04.mx.aol.com (mailoutv42.9.) id z.ee2.72ae6c8 (43849)
for <[email protected]>; Thu, 7 Oct 2010 18:27:41 -0400 (EDT)
Received: from smtprly-mc01.mx.aol.com (smtprly-mc01.mx.aol.com [64.12.95.97]) by cia-dc04.mx.aol.com (v129.4) with ESMTP id MAILCIADC046-d3c94cae49563c4; Thu, 07 Oct 2010 18:27:37 -0400
Received: from webmail-d010 (webmail-d010.sim.aol.com [205.188.181.34]) by smtprly-mc01.mx.aol.com (v129.4) with ESMTP id MAILSMTPRLYMC013-d3c94cae49563c4; Thu, 07 Oct 2010 18:27:34 -0400
To: [email protected]
Content-Transfer-Encoding: quoted-printable
Subject:
Date: Thu, 07 Oct 2010 18:27:34 -0400
X-MB-Message-Source: WebUI
X-AOL-IP: 41.215.217.83
X-MB-Message-Type: User
MIME-Version: 1.0
From: [email protected]
Content-Type: text/plain; charset="us-ascii"; format=flowed
X-Mailer: AOL Webmail 32761-PHONE
Received: from 41.215.217.83 by webmail-d010.sysops.aol.com (205.188.181.34) with HTTP (WebMailUI); Thu, 07 Oct 2010 18:27:34 -0400
Message-Id: <[email protected]>
X-Spam-Flag:NO
X-AOL-SENDER: [email protected]
The email that I got that was from me, to me. Again do not open the link, I would feel horrible if caused anyones computer harm, again I also changed my email address for the posting.
hi! Jen!http://made-of.fr/to.php Best regards, ,[email protected]

Answer 1

The emails are almost certainly coming from someone else's computer, not from your account. This will be definite if you can't see any of these emails in any of your "sent mail" folders and only are finding out about it by mail bouncing back or someone telling you that they've received such an email from your email address.
This type of infection, which exclusively infests Windows systems, uses a technique known as "spoofing," (mentioned by the other posters) by which the virus or worm randomly selects an email address it finds on an infected computer. The virus/worm uses this address as the "From" address when it performs its mass-mailing routine rather than using the real email address of the user of the infected system. If your address happens to be the one randomly chosen, then anyone receiving one of these emails sees your email address as the apparent sender. In addition, if any messages bounce back (either because the address is no longer valid or the mail server finds the virus and rejects the message), you get hit with the bounce rather than the actual (unknowing) sender, even though the messages didn't come from your system and may be from addresses you've never heard of.
Here's an example; Jane is using a computer infected with a Windows email virus or worm. Jane is either not using an antivirus program or does not have current virus definitions. When the virus/worm activates and runs, it randomly searches the Windows address book and finds the email address of Bill. The worm inserts Bill's email address into the "From" portion of an infected message, which it then sends to Janet. Janet then contacts Bill and complains that he sent her an infected message. When Bill scans his computer, the virus checker does not find anything, because his computer is not infected.
There's nothing you can do if, as appears to be the case, the emails aren't coming from you. All you can do is notify all your friends and colleagues who have Windows systems and who would know your email address and get them to update their antivirus protection.
Regards.