Identification of QTP checkpoint vs Execution of QTP checkpoint

This problem has flummoxed many people over time of why their checkpoint doesn't pass when they use Regular Expression in standard checkpoints.

When one use regular expression in a checkpoint, (s)he expects that it should pass when property being verified changes.This is a correct assumption. After all that's what regular expressions are there for!
But care should be taken to distinguish between identification vs execution of checkpoint. If you are using regular expressions for a varying property and your QTP is generating error message then the most probable reason would be that QTP is not able to identify the object for which you have created checkpoint. [Remember when checkpoint fails QTP won't throw error message it will only pass the "fail" status to results]

Just make sure that you handle the properties used to IDENTIFY that object properly.