my forum has been messed up twice over the weekend by x0r the wanker he makes the site redirect we changed everything new files etc etc and he still got in

1 how does he do this
2 how can we prevent him gaining access again?
lenney Reviewed by lenney on . securing vb forum my forum has been messed up twice over the weekend by x0r the wanker he makes the site redirect we changed everything new files etc etc and he still got in 1 how does he do this 2 how can we prevent him gaining access again? Rating: 5