I have upgraded from 2.3.3 to 2.5.1 and get the following error message.
Warning: require(/home/hillsplr/public_html/hillslearn4profit.com/wp-includes/compat.php) [function.require]: failed to open stream: No such file or directory in /home/hillsplr/public_html/hillslearn4profit.com/wp-settings.php on line 117
Fatal error: require() [function.require]: Failed opening required '/home/hillsplr/public_html/hillslearn4profit.com/wp-includes/compat.php' (include_path='.:/usr/lib/php:/usr/local/lib/php') in /home/hillsplr/public_html/hillslearn4profit.com/wp-settings.php on line 117
I reverted to 2.3.3 and still get the same message.