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The Bottom Line
Messagefire is a clean, simple and effective anti-spam service for POP accounts. Its filters, which look for email path forgery, are pretty precise, but still produce some false positives. Unfortunately, Messagefire is no longer available as an individual product.
Pros
- Messagefire has a great spam detection rate
- Works with any email program
- Simple, reliable concept, easy to use
Cons
- Messagefire is not without false positives
- Supports POP accounts only
Description
- Messagefire filters a POP email account for spam.
- Collects mail from your POP account periodically and makes it available from its own POP servers.
- Detected spam can be quarantined or marked for filtering in your desktop email program.
- Mail quarantined by Messagefire can be reviewed (and recovered) easily via a Web interface.
- Messagefire analyses the route of an email (based on header lines) to determine spam.
- If the path of an email is unlikely and looks forged, chances are the message is spam.
- Messagefire also blocks mail from all but authorized countries.
- Individual senders can be whitelisted easily, and Messagefire recognizes forwarding addresses.
Guide Review - Messagefire Personal Edition - Spam Filtering Service
Contrary to what most other spam filtering techniques assume, Messagefire thinks that spam cannot be determined by looking at its contents. The one thing characteristic about spam is that its sender has to lie about its origin (to prevent complaints and consequences).
Since the path of any email can be reconstructed from its header lines, inconsistencies in this path will be striking. This (and a few other aspects) is also what Messagefire uses to determine spam. This sound great in theory, and it works well in practice.
A few persistent copies of spam still get through, and there are some false positives. Reviewing and reporting them or authorizing the sender is easy and convenient via the Web interface, though.
