Can i Mac address ban / ban a users computer from accessing my forum?

So for 2 years now my forum has had a member knows as "holden" that has had thousands of accounts and keeps getting banned, we ban him at least 5 times a day with new ip's ect and were sick of him, we dont want to close registration as we are still growing, can we ban his mac address or something? p,lease help

I don`t think you can.

You can set up registration where an administrator has to approve the account. After awhile, the member causing trouble could get tired of creating accounts, but not being able to use the forum.