virus or what?

[memoe]

i do tech support and i occationally come across this issue:

someone will call in and tell us they are getting email bounced back to them for invalid address. they say they are not sending the email and they do not even know who the recipient is. I usually tell them that may be related to virus and to do an online scan to bypass av prog. i am not sure if that is what is causing that issue and would like to know what is.

any help with this would be grateful
Thank you,
memoe

[JohnE.]

After they do an anti-virus scan are any viruses detected? If no, then the problem lies elsewhere and if yes, then there's your answer.

Welcome to TechIMO!

[nomaxim]

Many mass mailer type worms (MyDoom is the latest) will spoof the 'From' Field in the e-mails they send.

What happens is the virus will pick two e-mail addy's at random out of the infected systems address book. The virus will then send itself to one address and list the sender as the other address.

The person who owns the infected system rarely has their own address listed in their address book, so that addy won't be used.

Since the ISP's send the e-mail back to the addy in the 'from' field, well someone else gets it. In these cases some of the addy's are no longer valid.

I once got an infected e-mail back that had my addy as both the sender and reciept.

I'll say you are right on track with the answer your giving. It never hurts for them to do a scan just to be sure.

[no1_vern]

Welcome memoe,

To Techimo!

The very first thing I think of is that someone is using their Email to spam people. Unless the Email is brand new it is virtually guaranteed to be on someones list, and most likely has been sold to a spam monger who hides his email by using the victims email to spam other people. My guess depends on how long the email addy has been in existence, which service they are using, and if they use the email address to list themselves for "free services", get info, enter in contests, etc...

It could be as you suggested-a virus that replicates itself and mails itself to others in an attempt to spread.

Good luck in finding what ever it is.