Exchange Send Connector cannot authenticate with smtp.btconnect.com

[procyon1]

Hi,

We use exchange 2010 to route emails to the smtp.btconnect.com smarthost.

If we use no authentication on the connector, the vast majority of emails go fine, but occassionally some get labelled as spam and are rejected by BT servers before ever reaching the desired recipient.

In order to resolve this problem, general BT support suggested we should enable the authentication on the send connector, I have tried both "ourusername@btconnect.com" and "ourusername" with the same password that we log onto the BT website, but the exchange connector does not seem to be able to authenticate: I get an error:

"451 5.7.3 Require Basic Authentication."

I have also tried entering credentials that I know to be incorrect, and am receiving the same result.

Any suggestions where I should be looking for a resolution?

[Burkem5]

Hi there Procyon1

smtp.btconnect.com was never intended to be used in conjunction with SBS or Exchanges.

This is more than likely why you are getting spam bouncebacks,  I highly recommend setting up Exchange 2010 as its own outgoing server and setting up a PTR record (rDNS) on your IP to prevent your IP being blacklisted.

Here is a help and support article on rDNS

Thanks 

Burkem5