I am getting this error when I changed the php version on my Xoops 2.5.9 website to PHP 7.0. It works if left on PHP 5.6 but trying to change that to 7.0, 7.1, or 7.2 which are readily available on my dedicated server.

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Error : Error: Call to undefined function split())

So I reverted back to PHP 5.6 for now until I figure out how to get it to work on PHP 7

I tried to do it on a fresh install while PHP 7.0 is enabled and still get the error.

There might be a problem with some of your old modules.

Quote:
Was this only XOOPS, or did you also included any other modules?

As Mamba already stated, some part of your Xoops instalation (probably a module) is calling a deprecated php function:

http://php.net/manual/pt_BR/function.split.php

Oh okay. I will uninstall all but system and protector to which module causing the issue. I will follow up