Cannot get upload function to work reliably

1... There is no preview. If you have a folder with a number of photos the board browse function won't show a preview

2....It simply will not browse some folders. I thought it might be related to the size of all the files, so moved only one, which had been cropped and reduced, to my desktop. The browse / upload function would "see" most of the files on the desktop, BUT NOT the target photo

I'm not seeing anything like this
This is just a shot in the dark, but... Log out. Restart your computer, then log back in.. And see if the problem persists.