Ok, thanks grumblemark.
Was able to find the appropriate thread and followed the suggestion. THe error message has gone away.
As a gentle nudge to others with this problem....
a search on "Constant _FB_AVATAR_GDIMAGE_NOT" will bring up the thread with the fix.
NOTE: off-topic sidebar...
One more helpful hint... if your ftp app will not allow you to chmod the permissions to upload the edited file do yourself a favor and install the wonderful component called "eXtplorer". This is a great component for modifying permissions within Joomla admin in cases where premisssions changes are otherwise not allowed.
