Google Message Security for Google Apps Administration Guide - Manual (Page 182)

182 Message Security for Google Apps Administration Guide
Troubleshoot False Positives
On rare occasions, legitimate messages can be falsely filtered as spam (often
called false positives). Or conversely, messages might get past the filters and
reach users’ inboxes.
Some common reasons for false positives include:
• Filter levels are too aggressive.
The message might have characteristics that make it look like spam, such as
disclaimers, URLs, dollar signs, multiple exclamation points, and little or no
body content apart from a link, image, or file attachment. Depending on your
filter levels, these characteristics can increase the likelihood of a message
being caught.
In particular, aggressive category filters can falsely tag valid messages as
spam. Try lowering category settings, beginning with the Special Offer filter.
Businesses tend to receive legitimate email containing commercial content,
so false positives in this category are more likely. An aggressive Bulk Email
filter can falsely tag valid emails, too, but should do so less often than a
category filter.
• A listserv or news group server sent the message.
Mailing lists share many characteristics of spam. If the sender address is
always the same, for example, [email protected], add it to the user-
level Approved Recipients list.
• The message was sent by an automated email service and appeared
“spoofed.”
This might include a message from a group reservation or auction site. Add
these addresses to your Approved Senders list.
• The sender appears on the org-level or user-level Blocked Senders list.
Remove it from this list.
Examining the spam score in a message’s header can also provide clues to why it
was identified as spam. See “ Interpreting Header Fields” on page 401.
Troubleshoot Spam that Gets Through
If too much spam is getting through to users’ inboxes, follow these steps to
determine why:
1. Are the user’s category filters set high enough to catch spam?