If you encounter the “The folder isn’t supported because of its location Slideshow” error when setting the Slideshow option for the lock screen in Personalisation settings, it means that the selected folder/subfolder is considered unsupported by Windows OS for the Slideshow. This error occurs when the location or type of the selected folder is invalid, especially when selecting a special folder or its subfolders such as Desktop, Downloads, Documents, Videos, etc. Even navigating to the source folder manually may result in the same error. However, there are user-tested solutions to fix this issue. One method is to manually browse to the source folder path instead of using “Quick access” to select it. Another method is to select but avoid opening the image folder. If you are unable to open the Personalisation settings page in the Settings app, you can use Command Prompt as an administrator to access it. If your Lock Screen Slideshow is not working, it could be because the Windows Background Slideshow is not enabled. To enable it, go to Personalisation settings and select Slideshow from the drop-down menu. Note that Slideshow wallpaper can drain your laptop’s battery, so you can change the Power mode to save battery with Slideshow on.