That will depend on your setup. Anytime you restrict an activity to run a on specific property or properties, you must include the appropriate at_property token in the call to Target.
On the activity overview page, you can see whether or not your activity is restricted to a specific property (see marker #1 below). If it is, you need to include the required at_property token (marker #2 below). You property token will be different than the one displayed in the image below.
The best way to think about the at_property token is as just another parameter (f.k.a. mbox parameter) in your request to target. When an activity is setup with a property, it is automatically includes parameter-level targeting to restrict entry to those requests that include the appropriate parameter.
token to be present on any page where tracking occurs. In the event that the token is (1) not present, (2) not detected at the time of activity setup (within the VEC), or (3) not passed to the clickTracking mbox via the
function, the metric will not be incremented and will appear as "0."
I would like to know whether Target will work with Email for swapping images without at_property ? If no, then were do we need to configure the at_property in campaign?