You send a message to a @toast.net or sub-account email address and receive a bounced message with the following error:
554 Sorry, message looks like SPAM to me.
TOAST.net checks all incoming messages for spam content. If a message fails too many spam checks it is not accepted by our email servers.
Most of the time a hyperlink somewhere in the message will trigger the bounce. Remove the link from the message and try to send again. Be sure to check for links in your signature if one is attached to the message.
Another solution is to have the TOAST.net user add the sender's email address to their address book or Whitelist.