how to block users registerig with same ip
 

hi

how can we block users who are registering multiple times from the same ip

This is always better to do though your server settings or control panel settings with your web host.

But yes, you can do it through vBulletin.

AdminCP > Settings > Options > User Banning Options

Of course you will need to add every IP he / she is using.

Or you can try to install a mod that will allow him to only have 1 account per IP Address.

Indeed. That would be the easier way. As it happens I have coded such a mod for a client of mine and it works like a charm to prevent users create more than one account from the same ip.

Geez, why isnt this already implemented in vbulletin core