Since last night after a server reboot, we have been having problems sending emails to another exchange server in our company. Whenever we send emails to users on that server, they bounce with a "556 null byte in data" error. I'm not sure what this could be, or why it all of a sudden started happening. We are running Windows 2000 Server, Exchange 2000 on all servers, over a VPN connection to the remote office. I have tried disabling out BitDefender antivirus/antispam and that did nothing.Help!