NoteXOOPS 2.5.x includes a License System Key that is stored in /include/license.php This file has to be writeable by the Installation Wizard, the same way as “mainfile.php”. On most system the Installer is able to write files, but if it isn't, you will have to chmod /include/license.php to 777. Just like the mainfile.php, you have to be careful with this file in later upgrades. The file is chmod'd back to 444 when it is finalized. Do not write over this file, you can generate it again if you do by running the upgrade.
Tip Experienced XOOPS users may choose to add additional modules. Additional modules can be added to the /modules directory before activating the Installation Wizard. The Installation Wizard will install all modules at one time and can save considerable time vs. installing each of them one at a time later on.