I'm sure you checked this but can you access the web console of the ACIII? Just trying to make sure you have network connectivy. Make sure you input Subnet Mask, DNS server, and Gateway information in the network setup screen. If you are using a router then both DNS and Gateway info will be the same(192.168.1.1 or 192.168.0.1 depending on how your subnet is set up). Subnet should be 255.255.255.0
What is your SMTP server address?