Competent cutting of spam?

Question

Exim

Colleagues, could you tell me how to organize spam spam cutting on Exchange in a simpler and better way? Edge can’t cope, they don’t allocate money for paid products. At the moment, I installed a filtering server on CentOS in front of Exchange, configured exim + spamassassin + greylisting there. But spam leaks out, and a lot of legitimate emails end up in customer spam. How can the spam protection system be improved?

Answer 1

In general, I use the same scheme, but I would like to draw your attention to the fact that now a lot of spam has come from actually registered mail.ru, yandex, etc. accounts. Accordingly, they will easily crawl through all the gray listings and spam assassins. Here it is necessary to approach the analysis of the content of the letter, but in this case, commercial offers may also fly into the furnace.
In my case, it is implemented as follows:
1. There is an imap-folder spam where spam falls through filters (the user can find a letter there). In fact, spam is not deleted, but only marked as honored so that the client software does not show notifications for every
sneeze .
3. Если письмо вытащить из спама, то адрес и IP отправителя помещаются в белый список.
Не сразу конечно взлетело, но схема уже работает как часики и все довольны.