Preferences app launches fine and all but one prefs pane work well — the Desktop & Screen Saver preference pane yields the following message:
"Preferences Error. Could not load Desktop & Screen Saver preference pane."
I have tried deleting the com.apple.systempreferences.plist file and re-starting. I have also restored this file from a Time Machine backup. And I repaired permissions. Nothing helped.
Any suggestions appreciated.
Best Answer
Solved.
Deleted the file desktoppicture.db located in user/library/applicationsupport/dock. Then re-started. This restored the default wallpaper.
Even though my previous wallpaper displayed without issue, it apparently caused a problem for the Desktop & Screen Saver Prefs. I checked the jpg and it wasn't corrupt.
If I pick another image for my wallpaper the Prefs error returns, but at least for now everything is stable!
Many thanks to Kevin G. and Buscar for the suggestions.