I enthusiastically did the combo update to 10.10.4 this morning anticipating it would solve the wretched problem of the screen saver always reverting to National Geographic. But it has gone from bad to worse. Whatever source I choose - including ironically National Geographic - the screen saver is just a black screen with the time displayed.
iMac (21.5-inch Late 2009), OS X Yosemite (10.10.4)
Might be corrupted sceen saver preferences (.plist)
Open the Finder. From the Finder menu bar click Go > Go to Folder
Type or copy paste the following:
~/Library/Preferences/com.apple.screensaver.plist
Click Go then move the com..apple.screensaver.plist file to the Trash.
Restart your Mac then try the screen saver.
Might be corrupted sceen saver preferences (.plist)
Open the Finder. From the Finder menu bar click Go > Go to Folder
Type or copy paste the following:
~/Library/Preferences/com.apple.screensaver.plist
Click Go then move the com..apple.screensaver.plist file to the Trash.
Restart your Mac then try the screen saver.
Yes, I realised after I'd posted that this was the obvious first thing to try. There were in fact three different screensaver plist files. Deleting them all and restarting did solve the problem.
No more national Geographic. HOORAY!
Screensaver black after 10.10.4 update
