How does your spam filter work?

Email is an extremely simple communication tool, but unfortunately, it is frequently abused. Not only for the spread of viruses but also for unwanted advertising and phishing (scams). It is estimated that between 70 and 80 percent of global email traffic consists of messages considered unwanted. This results in significant annoyance and greatly reduces productivity.

Assessing the nature of a message, whether it is wanted or unwanted, is a complex process. If the software is set too strictly, there is a risk that desired messages may be blocked. If the software is too lenient, too many unwanted messages might slip through. It is crucial to find the right balance. Our spam filter uses several factors to make well-informed decisions during this process:

• What is the reputation of the sender and their Internet provider?
• Is the sender's mail server technically sound?
• Is the email technically correctly constructed?
• Is the sender a validated source?
• Has there been prior contact with the sender?
• What is the content (digital fingerprint) of the message? If it contains advertising for pharmaceuticals or requests for credit card details, the likelihood of an unwanted message is high.
• Etc.

By carefully weighing these factors, you will only receive the messages you're expecting. At least 99.98% of all spam is blocked. The percentage of legitimate messages that are incorrectly blocked is less than 0.0001%.