Many customers ask how to block certain attachments, especially potentially harmful ones. Here is how it works.
First of all you have to define a ruleset which you want to use. We call it a content filter policy. Select Presettings (1) and Add (2) to create a new one. Give your policy a good name for what it will do. Now you have to define the attachment types you want to give a special treatment. Click Add (3) and create a new definition. Please be aware your definitions are evaluated from top to bottom and first matching entry will be applied. So if you allow invoice_0815-GmbH_*.zip this should be on top of rejecting *.zip-entry.
