Chapter 5 - Tips

Managing spam requires constant attention, but there are many things you can do to reduce your workload. This chapter offers advice for setting your CanIt-PRO settings.

5.1 Don't Trust Sender Addresses

Many spammers use one-time disposable sender addresses. Many addresses are not even valid. So we do not recommend blacklisting addresses unless you receive many different spam addresses from the same address. Therefore:

Blacklisting individual addresses is usually not effective. Whitelisting known good addresses (for example, mailing-list sending addresses) can be very effective. The sender report may, however, highlight a persistent spam sender address which is worth blacklisting.

5.2 Don't Trust Sender Domains

Just as sender addresses are often fake, sender domains are too. However, some domains are known spammers and these can be profitably blacklisted. The tip:

Blacklisting entire domains can be effective under limited circumstances. Whitelisting known good addresses (for example, mailing-list sending addresses) can be very effective. Holding all mail from free e-mail services like Hotmail and Yahoo can be effective if you use it in conjunction with whitelisting of known good senders from those services. Use the domain report to help make these decisions.

5.3 Group High-Scoring Messages Together

We recommend that you set the default sort order to sort by Score, Descending. This groups high scoring messages at the beginning and low-scoring messages at the end of the pending list. This makes it easier for the spam- control officer to dispose of the messages.

Reduce the spam-control officer's work by sorting message summaries by Score, Descending. This lets the officer use the interface more effectively.

5.4 General Anti-Spam Tips

5.4.1 Use Receive-Only Addresses on your Web Site

Spammers love to extract e-mail addresses from Web sites, and not only do they use them for the obvious purpose of spam targeting, but also they use them as fake sender addresses.

Therefore, we recommend a general policy of publishing only generic e-mail addresses on your Web site, like info@roaringpenguin.com and sales@roaringpenguin.com. When you reply to inquiries, always use a real, personal e-mail address like dfs@roaringpenguin.com. This has two benefits:

1. If someone sends e-mail purporting to come from info@roaringpenguin.com, you know immediately that it is spam, and you can reject it. You can blacklist all your generic addresses inside CanIt-PRO.
2. If someone complains about receiving e-mail from one of the generic addresses, you can point to your policy and assure the recipient that the sender address was faked.

5.4.2 Do Not Reply to Spam

Do not ever reply to spam e-mail; such replies simply serve to validate your e-mail address. Similarly, do not visit Web sites purporting to offer opt-out services; they also serve to validate your address for further spamming.