the pins in the lock might be gone, but you can get a new lock barrel , from any good hardwear store, its not hard to fit, just open the door and unscrew the cover plate thats the one over were the lock and latch pops through when you turn the key two screws in it , when you have that off you will see the screw that holds the barrell in, its just under the lock bolt that pops out when you turn the key, unscrew it out, now you just push the barrell were you put the key in, and get a new onw of the same size at any good locksmiths shop, if you go to Utube and look up (how to change a euro cylinder on a upvc door) you will see how its done, not a hard job,, good look,
m, July 2012
