Spam messages are received. What can be done to protect server?
Make sure that SpamAssassin spam filter is enabled in Tools & Settings > Spam Filter.
If it is enabled, test it using the instructions from the article.
For further spam filter accuracy improving, it needs to be trained:
- Access mailbox using webmail or mail client.
- Move all spam messages to the "Spam" folder. This will make the SpamAssassin spam filter recognize spam more efficiently.
Note: Spam filter system is not activated until a certain number of ham (non-spam) and spam has been learned. The default is 200 of each ham and spam messages. Change this value with the help of this article.
Detailed information about spam filter configuration and improving of spam filter accuracy is available in Customer's Guide
Information about all available anti-spam tools is available in Administrator's Guide.
Keep in mind that if hosting offerings include mail services, mail server can be used for malicious purposes, such as sending spam.
To get detailed information on how to configure Outbound Spam Protection in Plesk please refer to following resources: