---- dataentry configoptions ----
type             : constant
name             : ALWAYS_ADD_USERTRACK
purpose          : Always add the tracking image to campaigns
allowed          : true false 0 1
default          : 1
status_s         : 
category         : statistics
----

Before 3.0 you had to enter [USERTRACK] in the campaign to make sure that opens were tracked. This setting will always add it, even if it is not in the campaign.