Windows can only use images that are actually available locally in the folder selected for the slideshow. In the screenshot, the Lockscreen folder is stored in OneDrive (cloud icon). If the pictures are only online, the lock screen cannot see them and shows the message that more pictures are needed.
To fix this and get the slideshow working:
- Open File Explorer and go to
This PC > Pictures > Lockscreen.
- Make sure all images in this folder are stored locally:
- If a file has a cloud icon, right‑click it and choose Always keep on this device so it is downloaded.
- Confirm there is more than one image file (for example, multiple .jpg files) in the folder.
- Open Settings > Personalization > Lock screen.
- Under Background, select Slideshow.
- Under Choose albums for your slideshow, remove any old entries if needed, then click Add a folder and select the
Lockscreen folder again.
Once Windows sees multiple local images in that folder, the warning should disappear and the lock screen slideshow will start using those pictures.
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