The handle on our UPVC window won't fasten down all the way to can't lock the window. I have checked and tightened up all the screws and everything looks identical to the other window on the other side. The handle works perfect when its open and all the metal locking mechanism seem to be working as they should be .
Again like other questions I have answered the main cause of this problem is the sashes have dropped because the glass needs re-packing (Toe & Heeling).