Put the site down for maintenance

cp mantis_offline.php.sample mantis_offline.php

This will prevent users from using the system while the upgrade is in progress.

Always Backup your code, data and config files before upgrading !

This includes your Mantis directory, your attachments, and your database. Refer to Section 2.10, “Backups” for details.

Copy the configuration files

To preserve your system settings, you should copy the files listed below to subdirectory config of the new directory. You might have to copy as well other custom files such as logo, favicon, css, etc.

config_inc.php, the Custom Strings File (custom_strings_inc.php by default, see Section 7.1, “Strings / Translations”), custom_constants_inc.php and custom_functions_inc.php

Execute the upgrade script. From your web browser, access

http://yoursite/mantisbt-NEW/admin/install.php

where mantisbt-NEW is the name of the directory where the new release was extracted

Provide required information for the upgrade

Click the Install/Upgrade Database button

At the end of the upgrade, review and correct any warnings or errors.