Fantastico is not installed at the default location
From CPanelDirect
The error was
Fantastico is not installed at the default location /usr/local/cpanel/3rdparty/fantastico. Either move the Fantastico directory from it's current location to /usr/local/cpanel/3rdparty/fantastico OR enable ioncube loaders in WHM -> Tweak settings.
Enabling ioncube did not fix it for me. Maybe it will for you. After looking I found cpanel now uses /var/cpanel/3rdparty/bin/php NOT /usr/local/cpanel/3rdparty/bin/php
After doing a php info I saw it did not have a php.ini file in the new location. The fix was:
cp /usr/local/cpanel/3rdparty/etc/php.ini /var/cpanel/3rdparty/etc
Other Possible Fixes
You may want to first try enabling ioncube in WHM->Tweak Settings
Second you may want to try to update fantastico with cd /usr/local/cpanel/whostmgr/docroot/cgi/fantastico/scripts/ ; /usr/local/cpanel/3rdparty/bin/php cron.php
Third you may want to rebuild cpanel's php with /scripts/makecpphp
Fourth you may want to try a cpanel update with /scripts/upcp --force

