Do you use blacklists like SPEWS? Do you provide spam filtering? Do you provide virus filtering?

In the past, we used Osirusoft.com's aggregate zone, which includes SPEWS to filter California.com's incoming mail for spam, but found that due to the large number of false positives, it wasn't worth continuing to do so.

We do use a number of anti-spam blocklists which are much narrower than SPEWS/APEWS, combined with ClamAV, and SpamAssassin, to deliver excellent virus and spam protection.

Regardless, we still recommend you NOT open email attachments that you were not expecting, and to install a virus scanner on your personal computer. There's always a critical window between when a virus is released, and when an antivirus definition is written, so no antivirus software will stop every virus. Only vigilance on your part will do that.