Spam Bots on forums

[PackerFanatic]

We have been getting slammed with bots signing up on our forums at RNFL and I was curious if there is any good way to stop this or slow it down. Luckily, they aren't posting anything, but they just keep coming. We use phpBB boards, we can't track IPs (since they don't post), and the usernames and e-mails are so different that it would be pointless to constantly keep banning them. Are there utilities out there that can check for this kind of stuff? Thanks :)

[Dutch]

Newer versions of phpBB have a "Visual Confirmation" checkbox in the Admin Console. If you don't have it, you should consider upgrading.

General Admin-->Configuration-->Enable Visual Confirmation to be exact in 2.0.16

[PackerFanatic]

I did notice that we had an update to do, I should check that out then.