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I installed EFS (Email Forwarding Server) as POP3 connector for exchange 2007. It works but after few hours I start receiving spam emails.

for example i receive email from one of my account abc@mydomain and this email is process by EFS to download it to exchange after few hours i start receiving spam email on my same email abc@mydomain,

this is my private email and i never receive any spam on this id before.

this happen only after EFS and email process in EFS.

this does spam is coming due to EFS or exchnage server 2007?

does any one else face this problem or not?


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up vote 1 down vote accepted

Wherever you downloaded EFS from, or any IP hop in between knows that you probably have an open SMTP connection at your downloading address and therefore can SMTP "ping" your mydomain and then sell the address off to spammers.

Did you have to register the download? Does the spam have a proper To: address or is it made up? If my guess is correct, that kinda creepy. You can configure your inbound SMTP server to only accept connections from your EFS address, but it is also possible that EFS is actually a malware trojan that sends its address to a spam house. If EFS is malware, it also has POP credentials for your source maildrop. Without decompiling EFS or sniffing all its IP traffic you can't be sure that this isn't happening.

This need not have been the action of the author of EFS, a remote download is subject to a "man in the middle" attack and the source site might actually have a clean copy.

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But i download it from main site... – user20989 Jun 27 '10 at 19:44

Well as the developer of EFS, I can categorically tell you it most certainly is not malware. I would suggest you only ever download from our web site and not from 3rd party sites (unless they reference back to us) You have to be careful, when downloading from 3rd party web sites if they ask you to "sign up" with your email address - if its a dodgy web site, they will instantly add the email address you signed up with to a spammers database. Only ever download software from reputable web sites. Cheers, James

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