Without warning all my C:\Pics folder "jpgs" now open in a small window. I have resized the windows and clicking the icon reopens full size that session, But i cant do this for all 10, 20, 500 pics.
What did i do to cause this or better how can i undo this so that when i click on a picture it open maximized window?

No properties to select as with shortcuts and the shift key works with the one pic. I need to reset the whole Pic folder.
Thanks for any suggestions...