I can't watch it when the computer is turned off and turned on again.

When the computer is turned off and turned on again, no pictures can be seen. Maybe the corresponding picture has not been cached after you close it, so you can't see the corresponding picture. If the pictures on the computer can't be viewed after being turned off, it may be that the view corresponding to your picture is damaged and needs to be repaired. I suggest you go to the corresponding computer repair shop for professional maintenance.