I have the most recent Windows 10.

I was at the site viewing and organizing my photos.  Moving some into separate folders listed which I could easily do.

All of a sudden they disappeared along with the view of all the photos.  The list of individual folders on the left of my screen with recent uploads above have disappeared. 

How can I get that view back?

I am able to view individual folders that already have pics in them but those still remaining are no longer available for me to see.

Moved from Apps on Windows 10