Converting VBScript's Err Object Source Property
Definition: Returns or sets the name of the object or application that originally generated the error.
Err Object Source Property
To determine which object or component was responsible for an error you can check the value of the Source property. This command assigns the Source property for the most recent error in the error collection to the variable $a:
$a = $error.source
When you run this command and then echo back the value of $a you should back something similar to the following: