1
If your server use cPanel and PHP8,Someone disable_functions setting escapeshellarg and escapeshellcmd
Look the url
https://forums.cpanel.net/threads/php-disable-functions.483161/The XOOPS 2.5.11-Beta2 phpmailer have a message
Error: Call to undefined function escapeshellcmd()
or
Error: Call to undefined function escapeshellcmd() in file /class/mail/phpmailer/class.phpmailer.php line 1447
How to fix it
/class/mail/phpmailer/class.phpmailer.php
find function isShellSafe
line 1445
Add
if (!function_exists('escapeshellarg') || !function_exists('escapeshellcmd')) {
return false;
}