Managing attachment and content filtering rules

A rule is a set of conditions that must be fulfilled by a file attachment for the application to apply the defined action to the file attachment or content of an email message.

For each attachment and content filtering rule, the administrator defines the following conditions:

• Parameters of the message attachment file
• Recipients and/or senders of the message
• Exclusions from the rule (if necessary)

You can specify the following parameters as attachment and content filtering conditions:

• Password protection of the file
• Keywords

  The application scans the text and subjects of messages for the presence of certain words that are prohibited in the organization. A list of regular expressions can be added to a filtering rule either manually or from a TXT file.

  The application does not scan text contained in attachments for words forbidden within the organization.

• File name and/or extension.

  You can specify full file names or use file name masks.

• Presence of macros in the file
• File size in megabytes.
• File format.

  The application recognizes the format of a file by its structure, that is, by the way it is stored or displayed on the screen. This allows you to filter attachments even if the extension of an attached file does not match the actual type of the file (for example, if the extension has been changed intentionally).

If multiple parameters are selected, the rule will be applied if the attached file or content of the message matches at least one of them.

The application can perform any of the following actions on filtered messages:

• Delete the message
• Delete the object from the attachment (or the attachment itself)
• Skip the message

If an attached file match the parameters of multiple rules, the application will apply the rule with the most strict parameters: delete the message, delete the attached object, or delete the entire attachment.

The application can apply filtering rules to messages to/from specific users or user groups.

You can drill down the attachment and content filtering rules by excluding messages from filtering. You can exclude messages from scanning as follows:

• By sender email address.

  The application will not apply the filtering rules to message attachments from the specified senders.

• By recipient email address.

  The application will not apply the filtering rules to message attachments for the specified recipients.

• By file name or file name mask.

  The application will not apply the filtering rules to attached files that match the specified names or name masks.

• By file format.

  The application will not apply the filtering rules to files that have the specified formats.