Problem

Is it possible to use a wildcard to block all senders from a particular domain for example *@sendersdomain.com?

Resolution

In order to block all senders from a specific domain Domain Classification should be used instead of Sender Classification. Just add ‘senderdomain.com’ there. In general, wildcards are not recognized from sender/domain classification and use of  *@senderdomain.com matches only the email address *@senderdomain.com