Greetings from Montreal,

I have a 1998 Altima (black) that I have had since September 1997.
I love this car.  It has been very good to me.

This past summer I noticed a small rust spot under the back driver's side
window.  It was a small spot about the size of half a dime.  I was quite
upset to see this because the rest of the car is totally rust free as I
rustproof it every year.

I consider it strange that a rustspot should develop so high up on the car.

Wanting to fix this problem I promptly filed (yes with a small file taking
it to bare metal) the spot a bit bigger than the rustspot and then painted
it with two coats of black touchup paint and a coat of clear coat.  I used
one of those double ended pencil type paint/clearcoat sticks.  It was a bit
difficult to get all the rust off near the top edge because it went under
the rubber moulding of the window trim.  I did my best.

9 months later I see rust forming throughout the whole area that I touched
up!....Aarghgh!

Questions:
1) What is the best way to stop the rust?
2) Can such a thing actually be done?

Any suggestions to bring the car back (or closer) to its original beauty
would be appreciated.

Thanks

Theo