The dual modes of the Metro style Start Screen and the old fashioned Desktop mode found in Windows 8.1 do cause problems for users, specially when it comes to selecting a background wallpaper image or photo in the Desktop mode, then when we go to the Start Screen we see a totally different wallpaper.
How can we synchronize both Wallpaper backgrounds? Just these simple steps.
Click on Settings, then Personalize.
Click on the desktop icon shown in the arrow, this way your background images will be the same in the Windows Start screen as well as the Desktop.
When you now go to your Start screen, you should now see the same background found in your desktop. This means that when you change your Desktop background, your Start screen background will also match.
Please note this feature is only available in Windows 8.1