HELLO THATS A VERY HARD ONE, UNLESS SOMEONE KNOWS BETTER, I WOULD TRY AND DRILL OUT LOCK OR, GIVE IT A GOOD WHACK SIDE WAYS A FEW TIMES TO SEE IF I COULD BREAK IT ENOUGH TO EXPOSE SCREW .
KEITH, October 2008
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I can answer this question...
how can i fix a broken lock on a double glazed window?