What's "relaying denied"? What's "over quota"? Never fear, find out here!
What's 'relaying denied'?
This error message is seen mostly when using aliases. If you have an alias that forwards to an outside address, it's possible that said address does not allow "forwarding". You should contact your ISP to make sure forwarding is allowed.
What does it mean if I get an "over quota" message?
It means that your account has no availible disk space left; and therefore no more mail can be written to your email file.
To remedy this, you will either need to buy more disk space, or delete some things (either old e-mail or files in your web directory).