Accessed from Configuration Preferences Purging
Purging is the moving of messages older than a set number of days to the Deleted Folder. This can be undertaken manually or automatically.
The settings here extend to all folders for the current user, but settings may be overridden folder by folder. See Folder Properties.
NOTE that purging will apply to any folder set to be purged, or not excluded (as above, in Folder Properties) from the overall purging configuration.
Click a Hot Spot on the image below for further information.