Any suggestions on how to remove painted wood screws from a deck?

I have slottedhex flatheaded wood screws that have been stained over and I cannot remove them with a six sided bit with a screw driver because of the stain or paint in the slots of the screws. The screws fasten the floor boards of the deck and have been painted over.Any suggestions on how to remove painted wood screws from a deck?
What I would do is buy a little can of paint remover. The kind I use is a citrus application that has no toxic fumes and it's relatively cheap...about $5.00 for a container. Dab some on the painted over screw heads....only do a few at a time, and let it sit until the paint and old stain becomes soft. then use a putty knife to clean the heads off and use whatever driver head you need to remove the screws.





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Be careful with a screw tap like the one person suggested, where you hit it with a hammer to pop it loose. This could snap the heads off of the screws, then you'll have another issue on your hands. Not that it's a bad idea, just use caution.Any suggestions on how to remove painted wood screws from a deck?
I've had reasonably good luck just putting a new philips screw driver into the heads of painted-over screws and hitting it with a hammer. The force is so large and concentrated on the paint that it usually squeezes up around the screwdriver. I haven't found any paint that was too hard to yield to this approach.





If you use one of those impact screw drivers (the ones you hit with a hammer) it will also twist the screw at the same time, readying it for removal using a drill/driver.
What I used to do for fasteners that got painted/waxed over on a submarine was a machinist scribe. Generally paint and similar stuff chips out of screw slots/holes.