Check the connecting ip-port to be vaild, also use /emailaddr <email-address> and /identd on <email-address> and try again to re-connect, if you keep having the same error contact to the IRCAnywhere help support because it will not be an mIRC fault, also check if you have any antivirus or firewall open, if you have disable them and re-try, if you keep having a problem try to connect into an other server to be sure that is not an general connection problem.