Microsoft has released one more update for Windows 7 to fix the issue that made the Desktop Wallpaper to appear as Black when set to “stretch”. This oissue first started happening when Microsoft released update KB4534310 to Windows 7.
Here is the changelog provided for KB4539601 by Microsoft. This is provided as an Optional update on Windows Update. You can also install the update manually by clicking on Download link provided.
This non-security update includes improvements and fixes that were a part of KB4534310 (released January 14, 2020) and also includes these new quality improvements as a preview of the next Monthly Rollup update:
Addresses an issue that might cause your wallpaper to display as black when set to Stretch after installing KB4534310.
To get the standalone package (offline installer) for this update, you can click here.