What it does not promise

No filter is perfect, and we write it down

You will sometimes read that an anti-spam stops "99.9%" of unwanted mail. We do not write that, and not out of modesty: the figure means nothing without saying which mail it was measured on, nor how many good messages were stopped along the way.

What we owe you is something else: nothing disappears. Two mistakes are possible, and you have the means to correct both.

A good message stopped

This is called a false positive. A supplier's invoice, sent from a badly configured server, sometimes looks like a scam. The message goes to quarantine, you find it in your list, you release it. Once the sender is added to your allowed senders, it will not happen again.

A bad message let through

That happens too. A well-made scam, sent from a clean server, with credible wording: no machine tells it apart from a real message. This is why the Bouclier does not replace vigilance — it makes it possible, by clearing away the other twenty-six.