Fatal error: wp-includes/vars.php on line 16
If you are upgrading to wordpress 2.9, you might get this error Fatal error: wp-includes/vars.php .
Some people get this error when they do an automatic upgrade. I got this error when doing upgrade manually.
Reason : Some of the files were not copied correctly. You would keep your wp-config.php and contents folder. Rest all the files and folders need to be replaced.

