The system requirements changed to MySQL 4.3 and PHP 5.3.
IMPORTANT! Remove the ‘installer’ directory when you’ve successfully installed Kimai.
When you update an existing installment, just replace the entire Kimai folder on your server. Additionally you need to make all ‘compile’ folders (also inside all extension subfolders!) writable for PHP. Writing permission must also be granted to the ‘temporary’ folder and the included ‘logfile.txt’.
For current versions (>0.8.0) when you installed Kimai via the UI-Installer (not by editing the ‘conf.php’) you need to keep the file ‘autoconf.php’. For older versions (at least version 0.7) keep the file ‘includes/conf.php’.
When Kimai doesn’t start the reason is probably wrong writing permissions on the mentioned files and folders! Users also encountered problems with older PDO version – see support forum for more detail
Our documentation has information about fetching the latest development version.