Undelivered mail messages

[Bert]

I have suddenly started getting a lot of emails of the 'message undelivered' type.'Undelivered mail returned to sender' from 'Mail Delivery System' for instance. Thunderbird identifies some of these as spam, but not all of them. I opened a couple and they were nothing to do with any email I had sent. I have been sending and receiving emails for a couple or more years and only had a couple of such messages before, which were genuine. I've now had about 10 in a couple of weeks. Is this a new tactic by spammers? How can I tell a genuine message? Will the two I opened have caused any damage (I did not click on any links)?

[Buenchico]

(Answer in 2 parts):

Possible causes:
1. A spammer is sending out e-mails to millions of addresses. In order to get people to read these e-mails, he trys to make them look as if they come from a 'real person' and inserts your e-mail address into the 'From' and 'Return Address' sections. (All of this will be done automatically by his computer. You're address is just picked at random from some internet site or other). Inevitably, some of these mails don't arrive at their intended address and get bounced back to the 'Return address' (i.e. yours). (While this will be annoying, you won't have anything to worry about. Even if you open any attachment on the returned mail, all you'll get is yet another ad for Viagra or whatever).

2. Someone is trying to distribute a virus by sending out e-mails labelled 'returned mail'. (Once again, e-mail addresses are either culled from the internet or pure guesswork by a computer). In most cases, opening the mail itself won't be a problem but opening any attachments could let a virus in. (Your anti-virus software should prevent this, however). This is a fairly crude way to distribute viruses and hardly ever used these days. With a bit of care you probably haven't got anything to worry about.

[Buenchico]

(2nd part - Sent after I've just spotted all of the spelling & grammatical errors in the first part!):

3. Simple, straightforward spam. (i.e. the spammer has just put 'returned mail' in the title line instead of 'Important Account Information" or whatever) If. when you've opened those mails, you've found ads for fake watches, etc then this will be the cause.

4. Someone has hijacked your computer! This shouldn't happen if your firewall is working OK but it's just a possibility. Some spammmers (and the vast majority of virus creators) are very careful to ensure that mail can't be tracked back to their computer. Instead, they route everything through someone else's computer so that it appears to come from someone who is totally innocent. While this could be the cause, it's highly unlikely - it's usually the computers of big companies which are at risk. If this is happening you'll know because you'll have constant internet traffic on your computer (which would probably slow your browser to a crawl).

So, you've probably got nothing to worry about but, just to be on the safe side, check that your anti-virus and firewall programs are fully up to date (and properly configured). Then run a full virus scan. In future, just ignore anything similar. (We nearly all get these types of mail, sooner or later!).

Chris