Attachment Blocking

Use the Attachment Blocking page to specify types of attachments to block from incoming and outgoing e-mail messages and actions to take on blocked messages. Attachments are blocked based on message MIME types and filename types. In addition to selecting the types of message attachments to block, you can define actions to take on blocked messages.

An attachment blocking folder exists for each e-mail domain and the attachment blocking options can be based on the current e-mail domain or the primary e-mail domain settings.

Use the Users Attachment Blocking page to search for attachment blocking types in the selected domain, access and edit attachment blocking types, add new attachment blocking types, or delete attachment blocking types.

Important: Remember to restart Queue Manager after making Attachment Blocking or Blocking Message modifications.

Domain: Shows the current selected domain. From the drop down you can pick any of the domains available to this administrative user account. (Primary and non-primary IP'd domains only)

Use. Drop down menu.
- No Filter. Select this option to disable all Attachment Blocking for this domain.
- Current Domain. Set by Default. Only option when only a primary domain exists. For non-primary domains use this option if you would like the attachment blocking settings to be different than the primary domain.
- Primary Domain. Select this option to allow the current non-primary domain to use the same attachment blocking settings as the primary domain.
Content. Attachment blocking types. See Adding Attachment Blocking Types, for examples.
Type. Select from File name or MIME type.
Action.Select the action to take on a attachment blocking type match:
- Replace Attachment to replace the attachment with a message that provides information about the blocked attachment.
- Strip Attachment to remove the attachment without a message that provides information about the blocked attachment.
Enabled. Select to enable or disable rules that you have added to the attachment blocking settings, without having to remove the setting.

Add. Select to create a new attachment blocking type. For more information, see Adding Attachment Blocking Rules.

Edit. Select an attachment blocking type that you want to modify, then click Edit to modify an existing attachment type.

Delete. Select an attachment blocking type that you want to delete from the current domain, then click Delete to delete the type.

Attachment Blocking Message

The message box includes a default message that provides information about the attachment that has been removed. You can also create a custom message that replaces attachment body content that has been blocked.

When an attachment is blocked and the Replace Attachment option is selected in the Action for match list (on the Add Blocker page accessed by clicking Add on the Attachment Blocking page), a custom message is sent in the place of the attachment to the message recipient.

Use:

Current Domain. Select this option to define attachment blocking messages specific to the current e-mail domain.
Primary Domain (default). Select this option to define attachment blocking messages based on the primary e-mail domain's message settings.

This message will replace the body of a blocked e-mail attachment:

Use the default message that is included in the message box or enter a custom message to send e-mail recipients when an attachment is blocked. You can include variables in the custom message:

%t to indicate the message type (MIME or filename)
%c to indicate the filename of the blocked attachment (if applicable)

The contents of the message box are saved in a file named ab-message.txt located in the appropriate e-mail domain's top directory. The message box text should only be edited from the Attachment Blocking Message tab and is limited to 924 characters.

Note: If you want to log messages from the attachment blocking feature, make sure that the Verbose Logging is selected on the SMTP Settings Page.