E-mail send back as failed delivery!

[susan]

Dear all,

I have a trouble with my mailbox which always sending back as below
message:

Delivery has failed to these recipients or distribution lists:

(e-mail address removed)
A communication failure occurred during the delivery of this message.
Microsoft Exchange will not try to redeliver this message for you.
Please try resending this message later, or provide the following
diagnostic text to your system administrator.

Delivery has failed to these recipients or distribution lists:

(e-mail address removed)
This recipient e-mail address was not found in the recipient e-mail
system. Microsoft Exchange will not try to redeliver this message for
you. Please check the recipient e-mail address and try resending this
message, or provide the following diagnostic text to your system
administrator.

The following organization rejected your message: mail.higbee-inc.com.

This Message was undeliverable due to the following reason:

The following destination addresses were unknown (please check the
addresses and re-mail the message):

SMTP <[email protected]>

Please reply to [email protected]
if you feel this message to be in error.

Those kind of mails always send to my user who never known and never
sent mail to those address.

That make me wonder how come? if user doesn't send mail to this
address but it send back itself as failed delivery.

Anyone, please help me with this.

I look forward to hearing from you.

Thanks,


Susan

 

[Nikki Peterson]

What I am thinking is that you are getting messages from systems that
have received an email that "looks" like you sent it. Spoof email is like
that. It appears as if you sent it.

When that system gets the email, it sends you a courtesy message to
let you know that it won't deliver the email. This is confusing to you
because, you didn't send it in the first place. Some bad guy just sent
a message pretending to be you.

Not much you can do about it, just delete the messages.

The following links may shed some light on the problem:

Understanding E-mail Spoofing
http://www.windowsecurity.com/articles/Email-Spoofing.html

Email "Spamming" and Email "Spoofing"
http://www.lse.ac.uk/itservices/help/spamming&spoofing.htm

E-mail spoofing - Definition
http://en.wikipedia.org/wiki/E-mail_spoofing

Nikki Peterson

 

[susan]

What I am thinking is that you are getting messages from systems that
have received an email that "looks" like you sent it. Spoof email is like
that. It appears as if you sent it.

When that system gets the email, it sends you a courtesy message to
let you know that it won't deliver the email. This is confusing to you
because, you didn't send it in the first place. Some bad guy  just sent
a message pretending to be you.

Not much you can do about it, just delete the messages.

The following links may shed some light on the problem:

Understanding E-mail Spoofinghttp://www.windowsecurity.com/articles/Email-Spoofing.html

Email "Spamming" and Email "Spoofing"http://www.lse.ac.uk/itservices/help/spamming&spoofing.htm

E-mail spoofing - Definitionhttp://en.wikipedia.org/wiki/E-mail_spoofing

Nikki Peterson




















- Show quoted text -

After read your links, it sounds as the kind of virus? Can it impact
to the network? What did you mean about "Some bad guy just sent
a message pretending to be you"?

Sorry to ask you again. Could you please help me to be precise on
this?

Thanks,

Susan

 

[Brian Tillman]

After read your links, it sounds as the kind of virus? Can it impact
to the network?

While some PC may indeed be compromised with a spambot, it's unlikely that
it is your PC and it will not affect your network.

What did you mean about "Some bad guy just sent
a message pretending to be you"?

Spammers harvest addresses they find, either on the Internet or by
installing software on poorly protected PCs, harvesting the addresses found
in the address books on those PCs. The spammers then use those addresses as
the sending addresses for their junk so that the mail doesn't appear to come
from their systems, but rather from the systems of the people whose
addresses they've hijacked. It's very easy to have mail appear to come from
any address you wish.

I notice that you posted your message with a gmail account. If that's an
account you actually use and not a throw-away address, it is now the target
if this type of harvesting.

 

[Nikki Peterson]

It impacts the network in that all the system messages get sent to you.
You get an increase in your email count.

What happens is, the email (sent by the bad guys) has your SMTP as
the sender address (even though you didn't send it). So, just like a real
mail sent via the post office, the return address is yours. The post office
that receives the SPAM email tries to be courteous and send you a
note to let you know that your email will not be delivered (for whatever
reason). Those are the messages that you are receiving. The courteous
messages that the receiving post office is sending to you.

Not much you can do about it. Just delete the system messages and
wait the storm out. I have found that it happens in waves and usually
subsides in a few days.

As a note, you should "munge" your smtp when you post to a public
group such as this, to avoid putting your legitimate SMTP out in
public.

Definition:
http://en.wikipedia.org/wiki/Address_munging

Munging your email address:
http://www.mailmsg.com/SPAM_munging.htm

See the following link for information on how to "munge" your SMTP:
http://www.clearswift.com/support/technotes/item.aspx?ID=1529

Nikki Peterson

What I am thinking is that you are getting messages from systems that
have received an email that "looks" like you sent it. Spoof email is like
that. It appears as if you sent it.

When that system gets the email, it sends you a courtesy message to
let you know that it won't deliver the email. This is confusing to you
because, you didn't send it in the first place. Some bad guy just sent
a message pretending to be you.

Not much you can do about it, just delete the messages.

The following links may shed some light on the problem:

Understanding E-mail
Spoofinghttp://www.windowsecurity.com/articles/Email-Spoofing.html

Email "Spamming" and Email
"Spoofing"http://www.lse.ac.uk/itservices/help/spamming&spoofing.htm

E-mail spoofing - Definitionhttp://en.wikipedia.org/wiki/E-mail_spoofing

Nikki Peterson




















- Show quoted text -

After read your links, it sounds as the kind of virus? Can it impact
to the network? What did you mean about "Some bad guy just sent
a message pretending to be you"?

Sorry to ask you again. Could you please help me to be precise on
this?

Thanks,

Susan

 

[susan]

It impacts the network in that all the system messages get sent to you.
You get an increase in youremailcount.

What happens is, theemail(sent by the bad guys) has your SMTP as
the sender address (even though you didn'tsendit). So, just like a real
mail sent via the post office, the return address is yours. The post office
that  receives the SPAMemailtries to be courteous andsendyou a
note to let you know that youremailwill not be delivered (for whatever
reason). Those are the messages that you are receiving. The courteous
messages that the receiving post office is sending to you.

Not much you can do about it. Just delete the system messages and
wait the storm out. I have found that it happens in waves and usually
subsides in a few days.

As a note, you should "munge" your smtp when you post to a public
group such as this, to avoid putting your legitimate SMTP out in
public.

Definition:http://en.wikipedia.org/wiki/Address_munging

Munging youremailaddress:http://www.mailmsg.com/SPAM_munging.htm

See the following link for information on how to "munge" your SMTP:http://www.clearswift.com/support/technotes/item.aspx?ID=1529

Nikki Peterson











After read your links, it sounds as the kind of virus? Can it impact
to the network? What did you mean about "Some bad guy  just sent
a message pretending to be you"?

Sorry to ask you again. Could you please help me to be precise on
this?

Thanks,

Susan- Hide quoted text -

- Show quoted text -

Thanks so much for all your kindly help. This problem happened the day
after yesterday and my user received nearly 100 of those kind of mails
but yesterday and today, it seems those mail have gone.

Thanks again,

Susan