When I see Windows doing something out of the ordinary for a basic Windows utility, I suggest running the
SFC /scannow utility. But since you have already done that and it found no problems, I suppose we will have to look somewhere else.
Photoviewer looks at many things before it opens pictures. It checks for any "suppression" keys or open only in app keys, or only in Browser keys and permissions. Also, an Anti-virus will look at the file first.
You might check the
Event Viewer to see if any Errors or Warnings show up around the time you try to open a picture.
It also opens a file in the temp section of your AppData\Local folder. Not sure why it would have trouble getting access.
You might open the Default Programs, Set Associations and check some of the file associations and see if Windows PhotoViewer is listed or something else. Maybe the driver for you video card, or some utility associated with it has altered the normal behavior.
In the Program Files folder (x86) and normal, there is a Windows Photo Viewer folder. It contains a ImagingDevices.exe file and
4 .dll files. So, has anyone suggested re-registering any .dlls?
You may want to wait for other input, but I would try re-registering those four .dll files. The link below tells you how, but post back with questions. I am not that familiar with the command but others are. I suggest this because there are entries all over the registry concerning PhotoView. If something had changed or removed one of those entries, the program may not work correctly.
Regsvr32 Edit: I just tried re-registering the 4 .dlls and only 2 would re-register... In the Admin Command Prompt Window, I changed directory to the Windows Photo Viewer folder. You may not have to do that for the two files that will register, depending on where you prefer to enter the path...