Some of the desktop icons, i.e., Yahoo, have reverted to generic "world globe" icons and have lost their "customized" appearances. How do I get them back?

Have you tried right clicking the icon, the choosing Properties/Change Icon? Sometimes the icon you want is one of the choice in the list. Other than that, I would try restarting your Computer, or re-installing those particular Programs that have lost their original desktop icon.

Actually I'm talking about the desktop icons on my BB 8700g

Have you tried changing the theme?

Oh, sorry about that. Yes...try changing your theme, or if that fails try re-sending your Service Books.

yes send your service books to your phone. that show fix it