All Properties Err Object Property:  Err.Source Implemented in version 1.0   object. Source [ = string] This property lets us determine the object or application that caused an error, and returns a string that contains its Class name or programmatic ID. Also used when generating errors in your code to identify your application as the source, using the optional [ = string] argument, as below. Code: <% On Error Resume Next Err.Raise 8    'raise a user-defined error Err.Description = "My Error" Err.Source = "MyAppName" Response.Write "An Error of the type '" & Err.Description & "' has been_                          caused by '" & Err.Source & "'." %> Output: "An Error of the type 'My Error' has caused by 'MyAppName'."