Hello
Thank you for your question and reaching out. I can understand you are having query\issues related to thumbnails not showing.
- Please try to Clear Thumbnails Cache
In File Explorer, right-click on C drive to choose Properties -> Click on Disk Cleanup -> Thumbnails -> click on OK.
- Please Check and set the visual effects settings of your Windows to show pictures thumbnails by following the below steps:
In the search bar, type View advanced system settings.
Select View advanced system settings.
In the System Properties dialog box, click on the Advanced tab.
Under Performance section, click Settings.
In the Performance Options box, click on the Visual Effects tab.
Under the Custom section, select the Save taskbar thumbnail previews and Show thumbnails instead of icons options.
- Run below DISM commands from elevated prompt.
DISM /Online /Cleanup-Image /CheckHealth
DISM /Online /Cleanup-Image /ScanHealth
DISM /Online /Cleanup-Image /RestoreHealth
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