5
check the /include/version.php file, it should say define("XOOPS_VERSION", and some Xoops version number.
Xoops 1.3.10 was released back in 2003 so unless your project is really old it is probably one of the xoops2 versions. If it is a newer version, it would make upgrading easier because its not the core you may have issues with, but the modules. Xoops 2 introduces the smarty template engine which xoops 1 didn't have. The upgrade of the core files and database structure is easy, but as always
Always do a backup of the Files and Database. Some would even suggest to test it out locally with wamp (
http://wampserver.com) . There is a version of Xoops before when core devs began started removing the deprecated functions, I don't remember what version that was, but i would suggest to go to that version first. Maybe someone else knows what version that is.
If you decide to go with xoops 2.5.4, the release notes (in the news article and also included in the full package) has instructions on what to do to upgrade your site. the updater has scripts built in that will update your database schema which makes it easy. but problems may occur and if they do or u got any more questions feel free to post them.
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