I followed the setup at http://www.howtoforge.com/perfect-server-ubuntu-11.10-ispconfig-3 when changing my server from X32 to X64 due to some system files becoming corrupted on the 32 bit setup. For the DNS server I imported the settings from my X32 files into ISPConfig3 and everything seems to work fine apart from I am unable to connect to the site setup in ISPConfig3's DNS via my local network, which is not an issue I had on the 32 bit system. I can access the site when connecting via an external connection and I have the router / firewall set to resolve to the server. I have no problem connecting to any of the other 4 sites that are on the server, so I am guessing it may be something in my DNS settings - but honestly I have no idea where to start as I cannot see any differences in the settings when comparing the X32 setup to the X64 setup. Any clues?