Test object properties are the properties whose values are captured from the objects in our application when QTP learns the object. QTP uses the values of these properties to identify run-time objects in our application during a run session. Property values of objects in our application may change dynamically each time our application opens, or based on certain conditions. We may need to modify the test object property values to match the run-time object property values. We can modify test object properties manually while designing our test, or use SetTOProperty statements during a run session.