Purging Archives settings do not apply to transactional messages.
Keep Archived Messages for How Many Days
This setting determines how long archived messages will be saved. Saving a message in the archives allows it to be read at a later date.
By default, your list is set to 0 (zero), or to keep archives indefinitely. If you set the list to not keep archives, no archives will ever be saved. This is the opposite of setting the list to 0 (zero).
Not saving archives conserves disk space.
Note: If you disable archive saving completely, users will no longer be able to receive digest versions of the mailing list, and duplicate messages will not be removed.
If you want your users to be able to receive digests, but do not want to keep archives, set the Archive Messages to Enable Merge Mailings setting to "Yes," and set Keep Archived Messages for How Many Days to "1". See Utilities: List Settings: Basic Information: Enable Features to save archives.
Keep How Many Messages Archived
This setting determines how many messages from the list will be saved in the archives. For example, a setting of 10 means that the previous 10 messages will be saved in the archives. Any old messages beyond the most recent 10 messages would be automatically removed.
By default, your list is set to 0 (zero), or to keep archives indefinitely. If you set the list to not keep archives, no archives will ever be saved. This is the opposite of setting the list to 0 (zero).
Keep Mailing and Clickthrough Data for How Many Days
This setting determines how long outgoing mailing campaigns to your list are saved. Granular per-member delivery and clickthrough data is only available for saved mailings. If you will need to refer to this data in the future, increase this setting
This setting plays an important role in controlling the growth rate of your database.
Note that server performance may decline if you keep mailing and clickthrough data for a very long time for many of your lists.
When choosing a setting, you should consider how far back you plan on targeting mailings based on receipt of previous mailings or on clicks and opens . If you do not plan on targeting members using these metrics it may be wise to cap your database growth rate by selecting a value such as one year, also keeping in mind that the longer certain metric data is kept the less relevant it may become to you based on your individual business goals. By default, Listmanager does not purge aggregated statistical data on mailing and click/open trends so that information will still be available to you under the reporting section of Listmanager to help you guide your mailing campaign decisions.
It is important to be aware that large databases can become difficult to back up and restore in case of an emergency, which can increase your downtime in the event of a systems failure. Large databases are also difficult to move between servers, making upgrades more painful.
We recommend keeping an eye on your database growth rate based on your sending volume. If you are a high volume sender mailing to millions of recipients per month you will have a high growth rate, but if you are low volume your database will grow at a slower pace. If you are a systems administrator you may wish to monitor your database using tools of your choice and encourage list administrators to cap mailing data collection based on what you are comfortable supporting. If you are a list administrator noticing declined systems performance, you may want to make your systems administrator aware so that a database size policy can be implemented.