Antispam filters
On the occassion of discussion about SOPA, ACTA and a few other scary-sounding names we decided to focus our users' attention on another problem - sending spam and viruses via infected computers.
The problem is serious, because network which sends spam may be added to so-called RBL (Real-time Blackhole List). RBLs are servers that collect information about networks that send spam. In the effect sending emails from that net is blocked all over the world, because every serious admin uses RBLs.
Therefore our network has got protection against resending spam and viruses. We are using proxy, which scans all outgoing mail for viruses and whether or not they're spam. Only mail sent via default port (25) is scanned, because it's used by spambots the most. Port 465 (encrypted mail) and 587 (authorized mail) are not filtered. Also emails sent via webmail isn't filtered.
Users usually don't even know that their computer has been infected and that it sends spam and viruses. He'll find out when he tries to send email with his e-mail client. He'll see announcement:
What now? Surely we'll call that user, ask him for cleaning up his computer and blockade will be taken off. Single user that sends spam works on harm of all users, so our reaction will be fast :)
However, it may happen that mail will be classified as spam unfairly. We use high-class software, but no program is infallible. In that case user will see this announcement:
What can you do now? Call us and your smtp will be unblocked. Some users often send mail that will be recognized as spam wrongly (it happens when email consists of a picture with no text - spambots sends mails like this very often). In that case user will be excluded from filtering.
It might happen that you'll see this announcement while sending large amount of emails - in that case all you have to do is to divide your mails into smaller parts.
Undoubtedly spam is bad part of internet, nobody likes when his mail box is flooded by tons of unwanted correspondence. I hope that thanks to this tutorial our users will have greater awareness how to fight it. :)