FILTERING RULES

As each message arrives, it is subjected to filtering rules in the following order:

• If the message is perceived to contain a virus, it is automatically discarded. Viruses are messages with attachments of the form: .exe, .pif, .lnk, .scr, .cmd, and .bat. Such messages can not be sent to a mailbox that is Scrubbit-protected.
• If a message is listed in your "blocks" list, it is automatically discarded. This list can consist of specific email addresses, specific domains, or "wildcards" - such as all domains ending in a certain pattern. For example, it's possible to automatically discard all messages from China (i.e., those with domains ending in .cn).
• Messages longer than a certain length can be discarded, thereby avoiding the problem of clogging your mailbox. (Note that the term "discarded" here means that the message is placed in a holding area, and is only really thrown away after a period of several days. See notes below on what happens to discarded messages.)
• If a message is listed in your "friends" list, it is automatically accepted (provided none of the above rules have already caused it to be discarded.). Like the block list, friends can consist of specific email addresses, specific domains (e.g., @syv.com), or "wildcard" domains (@*.ru means any domain from Russia, for example.)

• If selected in your configuration, Scrubbit checks to see if the "To:" address of a message is one of your valid email addresses. Up to four email addresses may be specified as specific to your mailbox. (Note: it is possible for users to have "aliases", thereby allowing up to four actual email addresses to be associated with your email address. Many "spammers" blast out emails without including each email address in either the "To:" or the "Cc:" field of the message, thereby causing the message to be discarded. Note that there are cases, such as with distribution lists, where you might actually want to receive messages in this case, and it is recommended that you include senders to such distribution lists be included in your "Friends" list.
• Some spammers don't put a valid "From:" address in their messages, which should actually be contained in two different places in the header of each message. If this isn't the case, the message is discarded.
• A "real" name (not a null field) requires that an actual name (not just the email address) of the sender must be present.
• Messages can be sent through the Internet via SMTP servers that act as "relays", or postmasters. In cases where messages are transmitted world-wide, for example, a large number of "relay" servers may be used. It is recommended that this maximize at 2.
• Each message is subjected to "content analysis" to see if certain "objectionable" words are present in either the Subject or the Body of the message. If so, the message is discarded. The "objectionable" words are obtained from a system-wide "bad words" list, which is maintained by the Internet Service. (Future versions of Scrubbit will allow private versions of the "bad words" list on a per-user basis.)
• The "Max CAPS" trigger - one of the give-aways of SPAM messages is a large number of capitals in the subject field. For example, a spam might contain "REFINANCE NOW". This triggers the discard of a message if there are more than the specified number of capital letters in the subject field.
• The "Max Spaces" trigger - often there are special tags on the right-hand side of the subject field, separated by 20 or more spaces. This is a give-away that the message is being broadcast to a mass mailing list, so the message is discarded.
• The "Max Digits" trigger - Since spammers often open and close email accounts frequently, they include digits in their email addresses - and this is a give-away that it's a temporary account. For example, advert123@aol.com might be a temporary account. You can set the maximum number of digits tolerable in an email address before the Scrubbit filter decides to discard it.

To set your configuration options, login to the Scrubbit administration menu and click on the appropriate entry, then click Update to save the settings.