When I open an image in PS CS5 it now only shows it with lots of small white and grey boxes. This has not happened before and I have tried lots of my images which were fine before 2 days ago. I have installed all the recent updates, still the same and clicked again on open in history to no avail. Also tried opening through photoshop and ACDsee which is my normal route. Cannot view the images through Photoshop to work on.