What the f#@k is that?? I know it looks like an abbreviation for something that starts with "fuck you..." but what does it mean, for real? If you mail AOL and you're getting DNS errors back or the others like RLY: or RTR:, you have a few things you can check. One is to check if you have a "fully qualified domain name" or FQDN. Here's the lowdown on what it is:
