That was because I loaded ip-addresses with userid=-1.
And in admin panel I can see only addresses loaded by myself.
So it's OK now.

ipbans made by a userid not found in the user table will not be shown, this was by design.

I have found a nicer fix for the -ve values returned by long2ip; it will be appended to the first post shortly

just updated but still having the same issue. when i add an ip to ban it gets written to the DB but does not dispaly when I click "list IP bans"

What userid is listed alongside the ban?

I have installed this plugin on a vbulletin 3.8.3 forum, but I'm having a bit of trouble. The install went fine, and I can add new IPs to the ban list, but I cannot list current bans.

Whenever I click on "List IP Bans", I am met with an empty table and this error message:

Warning: mysql_fetch_array(): supplied argument is not a valid MySQL result resource in [path]/admincp/ipbans.php on line 36

Any ideas?

That suggests a mysql error in the preceeding query.

What version of mysql are you using?

5.0.51a

For those who cannot see added bans, check if mysqli is running.
I was playing around with it a few days ago and left it enabled, yesterday
i saw that all saved ipbans were gone (not showing in list).

it took me quiet some time to find out that

config.php
caused it..

.. and everything is fine

that fixed the vanishing IPs and the "Warning: mysql_fetch_array(): supplied argument is not a valid MySQL result resource in [path]/diaf/ipbans.php on line 36" error.

Its a pity because mysqli is the preferred and more efficient way to call in php 5x

For those running mySQLi - here's the fix

in ipbans.php

find
replace
.. thanks for the pointer, gmerin