I suggest you use Message Rules to filter out advertising.
In Outloook Express, find Tools>Message Rules>Mail>Mail Rules>New (or whatever the labels are in Deutsch).
Now make a new "Message Rule". Every time an incoming message contains the word 'Viagra' (or any other word or phrase you define), you can define how you want it treated:
(a) Don't download the email from your server at all.
(b) Immediately delete that email.
(c) Put the email in a special "Spam" (or any other name you want) Outlook Express folder, where you can review it later.
Give this rule a name like "Spam or Porn".
Add new bad words to the rule every time you see a new one.
I have done this for several years, and now can filter out almost all the spam before it gets to my Inbox.
Another rule which works well: make a rule for "Trusted Senders" who you know and trust. Make this rule the first one processed, and define the rule so that whenever the sender of an email matches a name you have entered for this rule, no other rules are processed. Transfer everyone in your address book to that rule. That way you won't miss a Viagra joke sent by one of your friends <g>!
Good Luck!!!