The Pictures Library is like a shortcut icon to your photos that are stored on your PC. It appears that something has stopped working correctly with either indexing/search. That problem can be looked at later. To find your photos, open file explorer and double click on the C drive or other partitions/drives then top right, in the search box type jpeg. In the list of photos shown left click one to highlight then right click and select "open file location". It will show the folder location top left. Scroll down further and try the same on another image as that one might be in a different folder. jpeg is the most common form of image formats but some can be BMP, PNG etc. You then know where to find these picture folders.
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