Pop-Up Dimension problems

Hi All, Excuse what is probably a really simple question.

I’ve created a pop-up in flash which has the dimensions of 800x500, however I want the pop-up to be bigger say 1000x700 but when I change the dimensions in the modify document settings and also on the code on the button which opens the pop-up it still opens the the same size???

Surely it should open bigger if I have asked it to and changed the dimensions as mentioned above in both documents including the code on the button.

And if I change the dimensions to 600x300 it should open smaller.

What am I doing wrong please help me.

Mark