We had the whole house double-glazed about 12 years ago by a well-known company. Some of the window handles were feeling loose and one stopped working completely, so I went to B&Q and got some Yale replacements. On three of the windows, the square hole into which the spindle fits is completely knackered (almost circular or actually disintegrating). Surely this doesn't mean some entirely new window frames just for the sake of a simple handle fixture. Is there any way for a DIY approach to this? I don't feel able to dismantle the whole window frame - can't see how to anyway.