davidfield1900 wrote:
I have a MacBook Air and a MacBook Pro. Both suddenly have turned all desktop thumbnail previews to blank white images. How do I get them to return to showing the thumbnails?
David
Did you try rebooting?
To trouble shoot further you can:
—Try a SafeBoot https://support.apple.com/en-us/HT201262
Takes noticeable longer to get to the login screen, does a 5-15 minute disk repair before it fully boots up, and certain system caches get cleared and rebuilt, including dynamic loader cache, etc. Login and test. Reboot as normal and test as caches get rebuilt.
In Safe mode third party system modifications and system accelerations are disabled, it removes malware, etc hampering smooth operation, however a reboot will put it back to normal mode.
This test will tell you if third party interference; extensions etc are not loaded in safe boot mode.
—Test issue in another user (or guest user) account https://support.apple.com/en-us/HT204443
This will tell you if it a universal issue or isolated to your user/admin account.