How to eliminate "halo" in images with transparent backgrounds

Question

I'm using DrawImage() to paint some images on a form with transparent background. Those images which are partly transparent cause a "halo" effect.(Look at the screenshot)

What's the best way to prevent that from happening

alt text http://www.imagechicken.com/uploads/1266798081003158300.png

EDIT

These same icons look great on my desktop so there should be some better way of painting the icons.

Answer 1

It's probably being caused by double rendering - the icon is rendering onto your transparent form, then the form is rendering over the background. Anyplace where your icon is only partially transparent, the form is losing all of its transparency.

Perhaps there is a change you can make to the form to support partial transparency rather than binary.