Thank you for the reply.
I can confirm that targz.php is present in core/lib
Also, there are no errors in the log related to loading the library. And I think the PHP config is OK based on the PHP info file I generated.
The interesting thing is I can perform a backup from System > Data > Backup/Restore. But when I do an export from System > Data > Import/Export, I see an error message (see screen capture). Even more oddly, I think the CSV exports are in the backups folder.
It appears the export is creating a .tar file in admin>system>backup and extracting it to a directory while displaying an error message. Any idea what the normal behavior of the CSV export should be?