Upgrade from 7.1.6 to 7.2

Hi while having the upgrade i got this error :

ALTER TABLE `bx_events_main` ADD `allow_view_forum_to` varchar(16) NOT NULL AFTER `allow_post_in_forum_to`;: Duplicate column name 'allow_view_forum_to'

any help much appreciated

Thanks

Do you have any added modules other than Boonex?

Yes i do