The image below shows the problem. Sometimes, Photoshop doesn't show the correct images to be exported. Here you see blank thumbnails, and the names of the Artboards are from a file I just closed, not the file I'm currently in. Before I closed that file, the thumbnails were showing the images from the other file, so I tried closing it to try stopping this behaviour.
To stop this, I need to close Photoshop and open the correct file again.
I'm on Windows 10 Enterprise, 64bit.
PS version is 2017.1.1 Release.
Have you tried updating the graphics drivers from the manufacturer website? also, you may try and reset Photoshop preferences back to defaults and see if that makes any differences.