this is not an error, neither a bug, only a notice upgrading to last 3.0.4.2 i get: Code: >> Update Operating System: Debian 6.0 (Squeeze/Sid) or compatible PHP Notice: Undefined index: timezone in /tmp/ispconfig3_install/install/update.php on line 99 This application will update ISPConfig 3 on your server. PHP Notice: Undefined index: timezone in /tmp/ispconfig3_install/install/update.php on line 99 and further if web module (mine is a multiserver) is installed: Code: PHP Notice: Undefined property: installer::$ispconfig_interface_installed in /tmp/ispconfig3_install/install/update.php on line 365