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Can I use wildcards like `*@spammer.com` in the anti-spam blacklist?

Short answer: No — the blacklist does not support wildcards or regular expressions. But you do not need them: every entry is matched as a case-insensitive substring of the sender address, so a single short entry can block an entire domain.

How matching actually works

For each incoming message, POPcon PRO takes the sender address, lowercases it, and checks whether any of your blacklist entries appears anywhere inside it. There is no glob expansion, no regex, no special meaning for *, ? or any other character. The exact same logic also applies to Recipient, Subject, Attachment, Header and free-text rules — they all use the same substring engine.

Concrete examples

  • Recommended: @spammer.com — blocks every sender from that domain. The leading @ anchors the match at the address boundary, so nicht-spammer.com or info@notspammer.com are not caught by accident.
  • Does not work: *@spammer.com — the asterisk is treated as a literal character, so only an address that contains the exact six characters *@spam… would match (basically never).
  • Too loose: spammer.com (no @) — this also matches legit.spammer.com.example.org or spammer.computers@othercompany.com. Always include the @.

Things to watch for

  • Case is ignored@Spammer.COM and @spammer.com behave identically.
  • Whitespace is NOT trimmed — a trailing space in your entry (e.g. from copy-pasting) will prevent any match. Make sure each entry is clean.

Bonus tip: clean up old "Display Name <address>" entries

Older blacklists often contain pasted full From-lines such as Max Mustermann <max@spammer.com>. These only match when the exact same display name is reused — the moment the same spammer changes it to Marketing Team <max@spammer.com>, the entry no longer fires. Replacing every variant of those entries with a single @spammer.com line both speeds up the lookup (one entry instead of many) and dramatically improves the catch rate, because any sender at that domain will now be blocked regardless of the display name.

The same advice applies to a 3000-entry list: collapsing per-sender entries into per-domain entries usually shrinks the list by an order of magnitude with no loss in coverage.


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