3
At Deny Sender, type the sender’s email address.
Users are not getting normal email messages.
Users might not receive normal email messages for several reasons:
• The email messages might be coming from someone listed in the Deny Sender list. You
might need to:
• Refine the Deny Sender list to ensure that wanted email messages are not blocked. For
example, you might need to type specific email addresses rather than ban a whole domain
or network.
• Add the sender, domain, or network to the Permit Sender list. The appliance does scan
email from senders, domains and networks in this list for spam. The Permit Senders
list overrides entries in the Deny Sender lists.
• The email message might have been blocked because it comes from a sender or organization
that has been recognized by one of your real time anti-spam lists as a potential source of
spam.
• The balance between blocking spam and normal email messages might need changing. For
example, if the appliance is blocking email messages when there is only a small chance that
they contain spam, you risk unintentionally blocking normal email messages. It is better to
risk letting some spam through.
• The email message might contain a virus or potentially unwanted program, and has been
blocked by anti-virus scanning.
Users are still receiving spam.
Users might still receive spam for several reasons:
• No anti-spam software can block all email messages that might contain spam. For the best
chance of detecting and preventing spam, ensure that the appliance is using the latest
versions of the anti-spam engine, anti-spam rules, and extra rules files, as well as using all
the features that can block unwanted email.
• The appliance is allowing streaming media to pass through.
NOTE:
Allowing streaming media to pass through the appliance is a security risk, because
streaming media is not scanned by the appliance. We recommend that you do not allow
streaming media of type
application/octet-stream or application/* to pass through the
appliance because these MIME types are executable and are a security risk
• Scanning for spam is not enabled on the appliance. Scanning must be enabled in the right
direction for spam detection. To detect spam from an external source, enable inbound
scanning. To detect spam from an internal source, enable outbound scanning.
• You might need a more stringent anti-spam policy. For example, you might want to ensure
that more email messages are marked as spam before they are received by users, or to
simply block the spam at the appliance.
• The email messages might be coming from senders, domains, or networks that are in the
Permit Sender list. Review the list to make sure that you really want email messages from
these senders to bypass anti-spam scanning. You might need to refine the entry in the list.
For example, rather than permitting whole domains or networks, specify individual email
addresses instead.
• The mail client software does not automatically move unwanted messages into a spam
folder, so users still see spam in their inboxes.
Troubleshooting
FAQ
49
McAfee Email and Web Security Appliance 5.1 Installation Guide
