Could you please post a screenshot with the Layers Panel visible?
Does turning off OpenGL in the Performance Preferences and restarting Photoshop have any bearing on the issue?
Please read these and proceed accordingly:
Thank you for your response.
I have turned off the OpenGL and restarted. It has worked! Thank you very much.
If you have the time, can you just explain what the OpenGL is and why it would do that to my files so I understand what to do if it happens again please?
In all likelihood it did nothing to your files but fouled up the diaplay.
And as turning off the GPU usage would cost you some features you should consider this not a solution but a method of identifying the cause of the problem – which probably is the GPU driver.
You may wan to try updateing the driver from the GPU maker’s site, not the OS maker’s site.
Ok thank you for your advice.