ColWidth, Mshflexgrid problem

I am trying to get the width of the last column in a grid. When I use the ColWidth property I get a value of -1 instead of the column width in twips. Other columns get this -1 as well. I can't use the ColPos property because it gives you the position of the start of the column. What is going on and how do I fix it?

Cheers, Brent