Mail routing with exchange 2000

I recendly changed the sofware settings on my symantec client for exchange security so that all suspected spam messages get redirected to my inbox.  

after doing this I have noticed that we are getting email sent to addresses with our domain extension but with invaild user names/ email address that never existed or that have long been deleted.

I do not understand how this is possible?

also when I run my backup on my exchange server I get an error message when it is trying to backup a mailbox that was deleted a long time ago and that i can not see in systme manager listed under mailboxes.
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This is a very common spam attack these days and is called Directory Harvesting.  

Spammers want to deliver mail to as many people as possible but they are only given ceratin amount of valid web address.  Once they know your e-mail domain exists, they reason that there must be other address in that domain also and so start generating e-mails to be sent to random address at that domain.

I work for a small 30 person company and we are blocking roughly 15000 - 20000 of these e-mails each week.

Those stories you hear in the news that 75% of e-mail traffic is is the reason :)

With regards your backup issue, remove and reselect what needs to be backed up and that error will disappear.  I have had that many times these past few weeks as I am in the middle of migrating users to new exchange servers.  After the user is moved, the backup job still tries to backup that mailbox from the original server.  As the user has been moved it also does not show up to deselect it.  Like I say, just uncheck the selected, select them again and save the selections and that error will dissapear.  
vlahomtAuthor Commented:
I understand the Idea of directory harvesting.  But what I don't get is how the emails get through if the email address never existed.  or is it just getting routed to me because the software is seeing it as spam and all spam is supposed to be routed to me.
How is the Spam getting through?

Well, to recieve incoming e-mails you have to configure exchange to accept e-mail for your e-mail domain, lets call it  Your server will accept ANY e-mail that is sent to the domain.  The mail server itself doesn't know what constitutes spam or anything like that, it's just accepts the lot.

Now then if you didn't have that redirector to yourself in the inbox and the spam software did not exist then all of these e-mails would end up as undeliverables with undeliverable messages being sent to the administrator inbox by exchange saying the mail could not be delievered.

I would guess that as this is the first time you have redirected the spam to yourself, you are only now coming to realise the volume of e-mail that exists and that your spam server has been filtering all this time.

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vlahomtAuthor Commented:
That is what I thought might be the case.

thank you for your help and explination.

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Windows 2000

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