One of the first things you need to understand is the Spam Score concept.
AS IceWarp Server processes messages with its many Anti-Spam technologies and checks, it modifies a Spam Score value dependent on the results of each test.
The Spam Score is a value from 0.00 to 10.00 that indicates the probability that the message is Spam, with 10.00 being an indication that the message is very likely to be Spam.
Some of the settings within IceWarp Server allow you to set a value to modify the Spam Score (for example - the Content Checks). The Value you enter in this section is the amount that IceWarp Server will modify the Spam Score by. So if you enter 1.5 for Score message containing blank subject and blank body then the Spam Score will be increased by 1.5 if that test evaluates as true.