Video Thumbnails Don't Display Unless I Refresh Explorer Window

Hi, I hope someone can help me!

When I open a folder containing video files, sometimes it won't display the thumbnails unless I back out of the folder and enter it again, or if I refresh the folder.

Sometimes it will load some files, for example if a folder has 5 files, it sometimes loads 2 but the other 3 are left blank, I have to refresh the folder to make the other 3 generate their thumbnails.

I didn't have this issue prior to Fall Creators Update. I haven't installed any video codecs or players.

I've ran the DISM.exe command, sfc /scannow and reinstalled all apps using powershell. I've tried turning off and on the display icons instead of thumbnails option, I've tried clearing thumbnail cache.

It happens on all disks, not a specific one.

Please help! It's driving me crazy.

I restored an image I made of Windows before the Fall Creators Update, I have no thumbnail issues with it. But if I update to FCU or install FCU from scratch, I have thumbnail issues.

I tried contacting Microsoft, who told me to do all what I had already done that I listed above, DISM, etc.

Thanks for the info. I gave it a try but it didn't work unfortunately. I don't get it, because video thumbnail generation is nearly instant prior to FCU, but slow and sometimes isn't loading them on FCU.

Another characteristic I noticed, is when it fails to load thumbnails, if I back out of the folder and enter any other folder, no matter how many, no video thumbnails will load until I refresh the original folder that I first entered.

Microsoft told me it's a problem with 1709 (Fall Creators Update) and to revert back to 1703 (Creators Update) as they are "working to fix all the issues with 1709", unfortunately I can't do that, I don't have an ISO and since I use Home, it'll update again. But the answer I got was vague, and I keep getting directed to Feedback Hub which I can't use due to work reasons.

I looked at this video on YouTube with a similar problem: How to fix COM Surrogate high CPU usage in Windows 10 - YouTube

Basically, the user had an issue with COM Surrogate using CPU, it turned out to be stuck loading a video thumbnail (WEBM).

So I downloaded a bunch of WEBM files and when I open the folder I notice that COM Surrogate uses over 50% CPU and the Explorer window will have a green loading progress bar in its address box, this lasts for about 8 seconds, but it doesn't load anything since Windows 10 doesn't support playing WEBM, so why is it trying to generate anything from them?

Just posting this info, in case someone can maybe point to something.

Also, I had the same issue on a Sandybridge (2600k) system, but clearing thumbnail cache seems to have solved it, but this isn't working on a newer Skylake system.

Suggest: Move the problem video files to an external drive then disconnect it and reboot to test.

Set folder options to not show thumbnails and use details view with preview pane enabled for all folders.

Turn off Automatic Folder Template Discovery.

For viewing multiple thumbnails use a third party image viewer instead of file explorer.

Suggest: Move the problem video files to an external drive then disconnect it and reboot to test.

Set folder options to not show thumbnails and use details view with preview pane enabled for all folders.

Turn off Automatic Folder Template Discovery.

For viewing multiple thumbnails use a third party image viewer instead of file explorer.

Leave problem video files on external drive and try converting one or more of them to a different format then copy the converted files back to your HD to see if you get the same issue with the newly created files.

Thanks for the info, although those suggestions didn't work. As far as I can tell, I've managed to solve it though.

I can't understand why it would work as a solution though, maybe someone can explain.

I deleted the thumbnail cache many times using Disk Cleanup trying to solve this, but I found a bat script written by Brink here:

Clear and Reset Thumbnail Cache in Windows 10 Customization Tutorials

I ran the second script (prompt), after restart, this fixes it every time. I can image/install Windows 10 again and have the bug, but if I run this script it fixes it (as far as I can tell so far).

Does the script do anything that Disk Cleanup doesn't?

Thanks again.