Windows is no longer creating new thumbnail images

Manually delete and rebuild the thumbnail cache.

Restart Windows Explorer.

Clear the thumbnail database using Disk Cleanup or Command Prompt.

That usually means your thumbnail cache is corrupted or Windows Explorer settings changed—try clearing the thumbnail cache with Disk Cleanup and make sure “Always show icons, never thumbnails” isn’t checked in Folder Options.

I've had times where simply clearing the thumbnail cache and restarting helped immediately. Other times, I had to run the system file checker or tweak some Group Policy settings.

It is often caused by corrupted thumbnail cache.

Make sure Windows is set to show thumbnails, not icons:

Open File Explorer > View > Options > Uncheck "Always show icons, never thumbnails" > OK/Apply.

Open Run menu and copy-paste cleanmgr and hit the Enter key.

Select C Drive.

Select Thumbnails and click OK.

Restart your PC.

You may also open Command Prompt as Admin and copy-paste the following commands:

taskkill /f /im explorer.exe
del /f /s /q /a %LocalAppData%\Microsoft\Windows\Explorer\thumbcache_*.db
start explorer.exe

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