Stop Your Mac From Changing Wallpapers Automatically
Your Mac gets annoying when it decides, “Hey, we’re not really going to use this image anymore” and automatically reverts your wallpaper back to system defaults. Fortunately, there is an easy way to protect your OS from scams.
Why is macOS restoring my wallpaper?
The issue has to do with how macOS remembers which photos to use as wallpaper. This is very finicky: if the photo isn’t completely downloaded to your Mac and saved somewhere the OS can work with, chances are you’ll lose it the next time you restart your computer.
One of the common problems described in this Reddit thread is that you select a desktop image from the Photos app when using iCloud Photo Library. By default, iCloud Photo Library optimizes the images it saves on your Mac, which means it doesn’t store full-resolution copies on disk when it doesn’t need to. It’s an effective strategy for freeing up space on your Mac, but it means your photos aren’t reliable choices for desktop images. macOS won’t dive into iCloud Photo Library to retrieve a photo if it loses it on your Mac, meaning it will be forced to replace the desktop image with the default image.
However, this is not the only reason why something goes wrong. Sometimes macOS loses your photo if it’s not in the folder it normally pulls desktop images from. This is why you sometimes lose your desktop image if you right-click on it and choose “Set Desktop Image”. If you move the image later, or if something else “shorts” macOS, it won’t be able to display the image.
How to prevent your Mac from automatically changing wallpaper
The best thing to do with all the pictures on your desktop is to move the selected photo to the Pictures folder on your Mac. Not the Photos app, mind you – I mean the Pictures folder you’ll find in the Finder sidebar. This is a trusted folder that macOS will be able to monitor for remembering desktop images. If you’re using a photo from the Photos app, export it to the Pictures app in the highest possible quality.
From there, open System Preferences > Desktop & Screen Saver, expand the Folders drop-down list, and select the desired image. This method is more reliable than dragging the image into the wallpaper preview, and even better than right-clicking on the image and selecting “Set as wallpaper” because you tell macOS via System Preferences exactly where the file is.
However, if the problem is simply that macOS is changing your wallpaper at regular intervals , that’s a different setting. Under Desktop and Screen Saver , make sure “Change Image” is not enabled. This setting changes desktop images from every five minutes to once a day, and when you log in or wake up from sleep. Disable this option to permanently save one selected image as wallpaper.