When you first use your GMX mailbox, your personal spam filter is still empty. Your personal spam filter is not trained until you click Spam or Not Spam to move incorrectly saved emails into the Spam folder or the Inbox folder. The same occurs if you move emails to the Spam folder or the Inbox folder by drag & drop or using the Move button. The spam filter remembers the following properties:
If you receive another email from the same sender, or an email with a similar text pattern from another sender, the email is automatically saved in the appropriate folder.
To ensure that your personal spam filter functions perfectly, you have to move emails incorrectly saved as spam, and undetected spam mails to the correct folder. If certain emails are saved in the wrong folder repeatedly, you can reset the spam filter in the Spam Protection settings to solve this problem.
The text pattern component in your personal spam filter works with wordlists that are created from the emails you have selected as Spam or Not Spam. The filter determines the frequency with which words occur in the selected emails and creates a custom model for your mailbox. This model is used together with the probability methods to classify new emails as wanted or unwanted. Put simply: the more often a word occurs in wanted or unwanted emails, the more it is weighted during filtering.
Your whitelist is also processed before the spam entries in your personal spam filter. Example:
If you use POP3 to access your email, you should set your email client or your mail app to leave copies of the emails in the GMX mailbox. You can then log in at gmx.com and move incorrectly classified emails to the right folder using the web interface.
If you access your emails using IMAP, you can move incorrectly classified emails to the right folder directly in your email client or your mail app. Your personal spam filter remembers the text pattern of the email, but not the sender address. To train the spam filter optimally, you must log in at gmx.com and use the web interface to move the incorrectly classified emails to the right folder.