QTP unable to identify pop up window

Solution: 
The problem here is that the parent object does not have a "visible" property enabled by default which leads to the situation that while running QTP is not able to identify pop-up window. So here are the steps to resolve the problem.

1. 1) Identify the parent object class.
2. 2) Got to Tools > Object identification.
3. 3) Select Environment.
4. 4) Select Test Object Class as identified in 1) above.
5. 5) Go to mandatory properties.
6. 6) Click on Add/Remove.
7. 7) Select "visible" property.
8. 8) Record the part of your application again.
9. 9) Now QTP should be able to identify the pop-up window.

Please let me know through the comments below if this solved your problem.