Forum please i need help when i do upgrade from 381 to 400
 

when i do upgrade from vBulletin 3.8.1 to 4.0.0
i get this error

Database error in vBulletin 3.8.1:

Invalid SQL:
ALTER TABLE post ADD INDEX ipaddress (ipaddress);

MySQL Error : Duplicate key name 'ipaddress'
Error Number : -1
Request Date : Saturday, January 30th 2010 @ 11:22:51 AM
Error Date : Saturday, January 30th 2010 @ 11:23:05 AM
Script : http://www.@@@.com/vbnew/install/upgrade_400a1.php?step=12
Referrer : http://www.@@@.com/vbnew/install/upgrade_400a1.php?step=11
Username :
Classname : vB_Database
MySQL Version :