There are several reasons why this might be happening, and we’ll address all of them in this article and provide effective solutions for each.
1. Disable Dynamic Wallpaper Settings
macOS comes with a plethora of colorful wallpapers, but they are divided into two categories: static and dynamic.
Static wallpapers are still, unchanging pictures, and they don’t change after a restart. But dynamic wallpapers change for a variety of reasons such as location or device activity. Most dynamic wallpapers have a light mode and dark mode variant, and automatically change depending on the time of day.
They can also change at preset intervals, or based on certain device actions (like when your Mac goes into Dark Mode).
If you set a dynamic wallpaper as your default, your Mac desktop background may change often. To fix this issue, turn off the dynamic wallpaper setting and use a static wallpaper instead. Here’s how:
Launch System Preferences from your dock or from the menu bar at the top of your screen. From the preferences, select Desktop & Screen Saver. In the Desktop tab, check the top-left corner. If you see three arrows in a cycle, your wallpaper is dynamic, and that explains why your desktop background changes occasionally. Scroll to the bottom of the Desktop tab and deselect the Change picture option. The Change picture and Random order options should be grayed, showing that the selected image is static.
2. Disconnect External Displays
If you have an external display connected to your Mac, it is possible that it will change your wallpaper setting, especially during reboots.
There’s no definitive reason for this, but it appears to be due to the difference in screen resolution sizes.
The best way to fix this issue is to:
Turn on your Mac and keep the lid open. Disconnect the external display from your Mac. Pick your preferred wallpaper and shut down your Mac. Restart your Mac while the external display is still disconnected.
Your wallpaper should remain unchanged, and you can now connect your external monitor. This appears to be the best temporary solution until a software patch is available for this bug. All you have to do now is make sure your external display is turned off before restarting your Mac.
3. Delete the Picture Database File
If neither of the above issues help you, the problem might be with your wallpaper’s database file. This file is titled desktoppicture.db, and it stores your Mac’s wallpaper configuration.
If the database file (or .db file) is corrupt, your Mac will have issues loading the wallpaper after a reboot and will opt for the default wallpaper instead. To fix this, try deleting the database file linked to your desktop picture.
Don’t worry, this isn’t a complex process, and deleting this won’t damage your device. Just follow these steps:
Open Finder and use the Shift + Cmd + G keyboard shortcut to open a command dialog box on your desktop screen. You can also click Go > Go to Folder to open this dialog box. Paste the following path ~/Library/Application Support/Dock/desktoppicture. db in the dialog box and click Go. This should immediately start Finder, which will redirect you to the folder containing your wallpaper’s database file. Select and Control-click on the Desktop Picture database file. Click Move to Trash to delete the file. Pick a static wallpaper and restart your Mac. macOS will create a new database file for your new wallpaper.
If this fix does not solve the issue, there’s one final potential problem your system might have.
4. Update Your Software
If the problem persists after you’ve tried all of the solutions above, you should update your Mac. Any corrupt system file responsible for the glitch will most likely be replaced by updating macoS.
Select System Preferences > Software Update. You should see the latest version of macOS update available. Click Upgrade Now to download and install it.
To make sure you don’t lose any important files and data during the update, you should back up your Mac before you begin.
Meet Things as You Left Them
With these fixes, your wallpaper should stay put even after you restart your Mac. All the procedures above are simple enough to do yourself, so give them a go before seeking professional help. You should find that your wallpaper stays put from here on out.
