When you are sending out e-mail, are you using a valid e-mail address on the server to send out from?
exists on your server and you are using mail.example.com
as your outgoing mail server and you are sending out mail from [email protected]
. Exim on your server (mail.example.com
) will see that the domain you are sending from (example.com
) exists on the server. It will then check to make sure that the e-mail address you are sending from ([email protected]
) exists on this server. If it does not then the transaction will fail, because the sender verification process will fail. If you do not have the [email protected]
e-mail address set up, then the default box will be checked. Setting your default box to :blackhole:
is the same as accepting the e-mail just not delivering it anywhere. So in this situation, any e-mail address on the example.com
domain will be seen as valid. When the default box is set to :fail:
only those addresses that are set up as actual mail account and/or forwarders will be accepted.
Basically, you need to insure that you are sending mail from a valid e-mail address that can also accept e-mail on the server.