Do you have backups? Antivirus? Antimalware? Have you checked for corrupt system files with SFC? All of these are things you should be doing, but you didn't mention any of these.
I have thousands of pictures saved on my computer. I pull up the folder they're in & do a search for a certain picture. The search results come back (By the name of the picture and a blank icon - jpeg in this case). BUT when I click on the actual picture, it says "File not found." Weird that it files come up in searches, but gives me that message. This is not for all pictures, but some. At one point, I had these thousands of pictures in one folder, but searches took too long. So I cut and pasted them into separate folders: A, B, C, etc .. (Since I name my pics). I researched this trying to find out why and of course was getting many internet results, but none of them addressed this particular issue. If anyone has any insight, it would be welcomed, some of these pictures are irreplaceable.

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