I'm on W10 and it's working fine but my external is on NTFS and maybe you need to try CCLEANERS cleanup and be sure to clean the thumbnail cache.
http://www.howtogeek.com/113382/how-to-use-ccleaner-like-a-pro-9-tips-tricks/
But Windows will have issues with some images. RAW ones may cause it to stop showing.
Win7, pc laptop.
Not sure what happened, but when I try accessing pictures on my external HD, not only do they seems to take Way longer to load all the way, but I'm now only seeing some or none of the thumbnails. Just that generic scene.
I've already tried the following:
-Folder options>View> Unchecked that 1st box about icons (in fact, it was *already* unchecked)
-broken down the number of images to other folders. The original had over 500. Still limited luck.
I'm at a loss.

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