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Documentation for Netmail Archive 5.4.
Documentation for [Netmail Archive 5.3] and [earlier versions of Netmail] is also available.

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The Attachment Management Agent lets you to strip attachments from email messages, allowing you to reduce storage bloat on your Exchange server and better manage your storage requirements. Each stripped attachment is replaced with an HTTP link that points to the original attachment. As such, you can manage email mailbox sizes by removing storage-intensive attachments from Exchange while keeping the attachments accessible to end users. The Attachment Management Agent also allows you to re-attach attachments that were previously stripped.


On this page:

Table of Contents



Selecting Attachment Management Job Criteria

After creating your Attachment Management Job and specifying appropriate Job Settings as described in Job Creation and Distribution, you are ready to select advanced Attachment Management Job criteria. First, click the name of the job you created earlier. By default, the Job Settings tab is displayed. The Job Settings tab allows you to configure basic settings for any of your jobs. The Job Settings tab is available on each Job Agent and is displayed by default when you click on the name of the job you created.

Click the Criteria tab. The Criteria tab allows you to specify what kind of Attachment Management Job you want to create. An Attachment Management Job can be configured to strip attachments from messages or re-attach attachments to their respective messages. In either case, you can specify what criteria should be met in order for attachments to be stripped or re-attached

Under Mode of operation, choose whether you want to Strip attachments or Re-attach attachments.

Stripping Attachments

The Strip attachments option allows you to strip attachments from email messages and store the attachments in Netmail Store.


Note: Netmail does not strip embedded attachments.


From the dropdown list, select the storage location in which you want stripped attachments to be stored. If the drop-down list is empty, you will need to create a storage location. For information about creating storage locations, refer to Specifying Locations.


Note: A Netmail Store or Netmail Store Emulator storage location must be used for attachment stripping.

Process from Primary Mailbox

This option allows you to strip attachments from those messages residing in users' live Exchange mailboxes.

Process from Archive Mailbox, if present

This option allows you strip attachments from those messages that reside in users' Exchange archive mailboxes.

Strip attachments only if message size exceeds [x] MB

Select this option if you want to strip attachments according to the overall message size. Enter the maximum allowed message size in MB. Only those messages that reach or exceed this size limit will have all of their attachments stripped.

Automatically expire attachments after [x] days

This option allows you to set the number of days for which attachments can be viewed after they have been stripped from a message. Once the expiration date is reached, the attachments are deleted. If the number of days is not specified, attachments will be kept forever.


Note: Archived items are retained for a certain period of time, and items in Netmail Store also have a particular expiry date. However, there is no direct correlation between archive deletion dates and attachment expiry dates. As such, it is possible that an archived message could contain a pointer to a stripped attachment in Netmail Store that has already expired. To prevent such a scenario, ensure that the lifetime of stripped attachments is longer than that of archived messages.

Place links to stripped attachments in the body of the message

If you select this option, links pointing to the stripped attachments in your storage location will appear in a table (in either HTML or plain text format, depending on the format of the message body) within the body of the email message they were stripped from. The following information will appear in the table:

  • Name of file(s)
  • Expiry date of the item(s)
  • Size of item(s)

The following screenshots show how a message looks like in a user's mailbox before attachment stripping has been implemented.

Outlook before:

OWA before:


The screenshots below show the same message after attachments have been stripped (with HTTP links placed in the body of the message). Stripped attachments can also be accessed through a small Attachments.htm file attached to the message.

Outlook after:

OWA after:

Re-attaching Attachments

The Re-attach attachments option allows you to revert back to the original message and its attachment(s). In other words, stripped attachments are re-attached to their original message rather than being linked to through HTTP links in the HTM file. Once the attachments have be re-attached, the HTM file is removed.


Note: This re-attachment mechanism does not re-attach attachments at the gateway. Rather, it simply re-attaches attachments to their respective messages in the Exchange mail server. For information on re-attaching attachments at the gateway (for outbound messages), refer to the documentation on Netmail Secure's Attachment Management Policy and Attachment Management Agent.


From the drop-down list, select the storage location in which the stripped attachments you want to re-attach are stored.

Process from Primary Mailbox

This option allows you to re-attach stripped attachments in their original format to their messages on the live Exchange system.

Process from Archive Mailbox, if present

This option allows you to re-attach stripped attachments in their original format to their messages residing in the Archive Mailbox.


Important: After specifying your Attachment Management Job criteria options, click Save to save your settings. If you do not click Save, your settings will not be saved.