> To  make  sure that no one can send mail remotely off of the server.
> For  the most part, it has worked very well, however a user with the
> sending  address of "<>" is always able to send mail off the server.

As  must  be  allowed, both per the RFCs *and in order to allow bounce
messages  to  be  returned  to  your  users*.  Apparently, you haven't
followed  the  hundreds  of  posts  on  this issue. Please look in the
archives  and  I  hope you are enlightened--you MUST allow the null <>
sender if you are going to operate a mail server exposed to the public
Internet  and  referenced  in  a  public  MX  record. (For the record,
'Refuse  Null  Sender,' one of the lamest options in IMail, will allow
you to disable this mandatory feature, so if it's still being blocked,
you  likely  have not restarted SMTP since making the change. Not that
it  matters,  since you have to uncheck it pronto--actually, according
to  my  recent  check  of your IP, <> is indeed blocked, so you should
have updated your post.)

However,  allowing  <> to send inbound mail does not allow <> to relay
mail, so your problems lie elsewhere. I can guess at exactly where you
erred.  You  probably are allowing 'Relay for Local Users,' given this
Telnet trace:

> 220 X1 NT-ESMTP Server mail.broadcastzone.biz (IMail 6.06 17-1)
> mail from:<[EMAIL PROTECTED]>
> 250 ok
> rcpt to:[EMAIL PROTECTED]
> 250 ok its for <[EMAIL PROTECTED]>

And  again, looking in the list archives and Ipswitch KB will tell you
that  the ONLY safe options for relaying are 'Do Not Relay' and 'Relay
for Addresses.' Otherwise, you are an open relay.

Now, this...

> 4.) All boxes checked in SMTP Security Tab

...is  just  crazy. In disabling SMTP AUTH reporting, for one, you are
in effect disabling SMTP AUTH from most mail clients. And checking the
'Allow Remote...' options DECREASES the security of your server.

You  need  a major primer in the way IMail operates, I'm afraid, which
only  the  archives  and  KB can give you. When you have some specific
questions, post back.

-Sandy


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