I am hoping for some advice, as to what we might do to prevent a user sending spam emails to other users via the forum.
We have run our phpBB board for a few years and never had this happen before, but in the last few days we've had a problem with a user sending spam emails to other users through the forum. Private messaging is disabled, email addresses are hidden, but we do allow emails to be sent via the board.
When we first became aware of these spam emails, we banned their account, and their (gmail) email address and their IP address (from the Ukraine), and also blocked their IP address at our own firewall. They then re-registered using a very slightly different gmail address, and started again with sending spam emails - so we again banned & blocked as we did with their first account (this time the IP address was Poland). They then registered again with yet another gmail and started sending spam again to users - again we have banned & blocked as before (the IP address this time is in Russia). We know its the same person/organisation because the gmail email addresses are just one character different each time.
We tried disabling the option for users to email via the board at all - but that stopped users being able to email admins too, and also took away a useful facility that genuine users like to have. So at the moment we are back allowing users to contact each other via the board - but are fully expecting this spamming person to start with a fourth account!
Is this just something we have to live with until they get fed up of being banned, or is there something else we can do?
Thanks for any advice!