[Dismounted]

$invitegroupid, as it stands right now, will return an array. And will not work as you want it to. You want to use $invitegroupid['NewusergroupID'].

Originally Posted by Vaupell

how can if ($vbulletin->GPC['invitation']) <-- do anything
shoundt there be a "if ($vbulletin->GPC['invitation'] = content )

The first will check if a value is true. True being one that is not null, not an empty array or string, or the integer 0 (a string that is "0" is not true). The second will actually assign the constant "content" (you were probably meaning to use the string, not the constant) to the variable. You were looking for the equivalence operator "==". This checks if the two values are the same (note that it will not check type).