uPVC window won't open

[GaryMo]

The square section of a multipoint locking mechanism where the handle on a uPVC window keys into has disintegrated meaning that when turning the handle the square peg has nothing to key into.
Is there an easy way of opening the window in this case so I can replace the multipoint locking mechanism?

 

[crank39]

Check other windows you know are of the same installation to see which way the cams/mushrooms move in relation to the keeps on the frame. Its probably safe to assume it has shootbolts as well, in which case...

1/ Remove the dgu from the jammed window, this give more scope for twisting and lifting

2/ Slide a flexible scraper/knife in between the opener and frame remembering where the keeps where and which way the mushrooms/cams move when you move the handle.

3/ Takes a bit of time but slide the mushrooms/cams out of the keeps with knife

 

[GaryMo]

Thanks very much for your advice, it's very much appreciated.

Here's a couple of photos of the mechanism from another windows of the same construction. There's two locking points, one near the top and one near the bottom.

 

[crank39]

Yeah you should be able to fiddle that open, pinch one of them there flexible spatulas from the kitchen draw