MagicSpam prevents email identified as spam from ever reaching your email account.
If included with your hosting control panel you may find that MagicSpam Protection is enabled by default.
Some customers tell us that legitimate contacts' mail has been blocked by MagicSpam when enabled.
Whilst MagicSpam can be controlled through active management on your part, unlike SpamAssassin it does not permit you to adjust filter settings.
Reason: it works in a totally different way.
You may therefore prefer to use SpamAssassin (if installed) in conjunction with Email Filters.