I tried this myself but I wasn't able to record my test so I used Descriptive Programming and it worked.
To get the number code of the General Run Error you are getting, try inserting
after the line where error occurred.
Code:
Dim desCalc
Set DescObj=Description.Create
Set desCalc = Description.Create()
desCalc("title").value = "Calculator"
Window(desCalc).Activate
Set childObject=Window(desCalc).Childobjects(DescObj)
msgbox childObject.count
For i=0 to childObject.count-1
childObject(i).highlight
msgbox childObject(i).GetROProperty("Class Name")
Next
To get the number code of the General Run Error you are getting, try inserting
Code:
msgbox Err.Number