In reality, few of the real spams that get through the UTM's anti-spam come from an address worth blacklisting. Those that come through repeatedly are usually mailing lists that the end-user opted into at some time - the answer is to opt out both from the particular emailer and their list provider at the bottom of the spam.
In reality, few of the real spams that get through the UTM's anti-spam come from an address worth blacklisting. Those that come through repeatedly are usually mailing lists that the end-user opted into at some time - the answer is to opt out both from the particular emailer and their list provider at the bottom of the spam.