The first thing I'd do is look in your .htaccess file(s) to see if it's blocking IP addresses, particularly those in the Low Countries. Do these users have anything in common, such as a particular browser or other USER_AGENT that you're blocking? How about within your message board -- does it block on any criteria, such as IP address? Perhaps there was a run of suspicious activity from a certain geographic area, and the board automatically blocked it? Check its admin area to see if it has any of its own blocks. Finally, it's possible that Lunarpages itself spotted certain activity, decided it was suspicious, and instituted its own blocks. You would have to open a support ticket to get those block(s) cleared, and may need to know the IP addresses. Suspicious activity could include trying to sign on to an account many times in quick succession, such as forgetting a password and trying a bunch of them. These look like "Denial of Service" attacks to the host.