1) run "gpedit.msc"
2) go to "User Configuration", "Administrative Templates", "Windows Components", "Windows Explorer"
3) enable "Turn off the caching of thumbnails in hidden thumbs.db files"
You can also try a different aproach:
Open the Registry Editor (regedit.exe).
Navigate to HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer\Advanced.
Double-click the DisableThumbnailCache value, or go to Edit > New > DWORD value to create a new value by that name.
Enter 1 for its value.
Click Ok and close the Registry Editor when you're done; you'll have to log off and then log back on for this to take effect.
Note: don't confuse with folder options "always show icons, never thumbnails", which disables showing thumbnails on windows explorer views (you will have to open the images to be able to see what they look like)