I have never seen this syntax used in Visual Basic 5 or 6 before. The compiler is trying to divide W by n by m (whatever W, n, and m are). You will get the divide by zero error no matter where you put the code. What exactly are the properties you are trying to set, and what is "usercontrol"? A text box, command button, etc.
An làmb a bheir, ‘s i a gheibh.