Open a command prompt and navigate to the folder containing your pictures. Type del *.db /s /as (without the quotes). This will delete all the thumbnail ...
If you want to delete the folder, you should be able to do that by disabling thumbnails first. In File explorer, click on View tab > Options. In ...
About This Article Click the View tab at the top. Check the Hidden items box. Click Options, and select Change folder and search options. Click the View tab in the Folder Options window. Uncheck the Hide protected operating system