Here is what Axigen support told me. Make any sense of it?
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Hello,
This provided solutions brought us to this point, where you encounter
this specific error.
This error is caused by a problem with the remote server, which is not
RFC compliant, as specified in our last email. A solution would be for
your ISP to provide another server that does not present this non-RFC
compliant behavior or provide you with an open relay (not request
authentication for emails from your IP).
The open relay is not the problem, but would be a solution, if provided
by your ISP for your specific IP.
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Although the authentication is successful the remote host "forgets"
this after the second EHLO command:
01-17 00:26:50 -0600 08 HPSERVER SMTP-OUT:00000001: Relay mail
18E2A0: connecting to 98.138.31.74:25
01-17 00:26:50 -0600 08 HPSERVER SMTP-OUT:00000001: Set remote smtp host to <[98.138.31.74]>
01-17 00:26:50 -0600 08 HPSERVER SMTP-OUT:00000001: Set remote smtp port to 25
01-17 00:26:50 -0600 08 HPSERVER SMTP-OUT:00000001: Use plain connection
01-17 00:26:50 -0600 08 HPSERVER SMTP-OUT:00000001: Set AUTH user to <
XXXX@swbell.net>
01-17 00:26:50 -0600 08 HPSERVER SMTP-OUT:00000001: Set AUTH password to *****
01-17 00:26:50 -0600 16 HPSERVER SMTP-OUT:00000001: 220 smtp101.sbc.mail.ne1.yahoo.com ESMTP
01-17 00:26:50 -0600 16 HPSERVER SMTP-OUT:00000001: EHLO HPSERVER
01-17 00:26:50 -0600 16 HPSERVER SMTP-OUT:00000001: AUTH LOGIN >> anNob2xsaXNAc3diZWxsLm5ldA==
01-17 00:26:50 -0600 16 HPSERVER SMTP-OUT:00000001: 334 UGFzc3dvcmQ6
01-17 00:26:50 -0600 16 HPSERVER SMTP-OUT:00000001: bWF0dGhldzIwMDM=
01-17 00:26:50 -0600 16 HPSERVER SMTP-OUT:00000001: 235 OK, go ahead --- AUTHENTICATION IS SUCCESSFUL
01-17 00:26:50 -0600 16 HPSERVER SMTP-OUT:00000001: EHLO HPSERVER
01-17 00:26:51 -0600 16 HPSERVER SMTP-OUT:00000001: 250-smtp101.sbc.mail.ne1.yahoo.com
01-17 00:26:51 -0600 16 HPSERVER SMTP-OUT:00000001: 250-AUTH LOGIN PLAIN XYMCOOKIE
01-17 00:26:51 -0600 16 HPSERVER SMTP-OUT:00000001: 250-PIPELINING
01-17 00:26:51 -0600 16 HPSERVER SMTP-OUT:00000001: 250 8BITMIME
01-17 00:26:51 -0600 08 HPSERVER SMTP-OUT:00000001: Start sending mail 18E2A0
01-17 00:26:51 -0600 16 HPSERVER SMTP-OUT:00000001: MAIL FROM:<
jerry@XXXXX.homeserver.com>
AUTH=jerry@XXXXXX.homeserver.com
01-17 00:26:51 -0600 16 HPSERVER SMTP-OUT:00000001: RCPT TO:<
XXXX@swbell.net>
01-17 00:26:51 -0600 16 HPSERVER SMTP-OUT:00000001: >> DATA
01-17 00:26:51 -0600 16 HPSERVER SMTP-OUT:00000001: << 530 authentication required - for help go to
http://help.yahoo.com/sbc/dsl/mail/pop/pop-11.html --- THE REMOTE SERVER FORGOT THAT YOU ALREADY AUTHENTICATED
01-17 00:26:51 -0600 08 HPSERVER SMTP-OUT:00000001: Negative reply to MAIL command: authentication required - for help go to
http://help.yahoo.com/sbc/dsl/mail/pop/pop-11.html
01-17 00:26:51 -0600 16 HPSERVER SMTP-OUT:00000001: << 530 authentication required - for help go to
http://help.yahoo.com/sbc/dsl/mail/pop/pop-11.html
01-17 00:26:51 -0600 16 HPSERVER SMTP-OUT:00000001: << 530 authentication required - for help go to
http://help.yahoo.com/sbc/dsl/mail/pop/pop-11.html
01-17 00:26:51 -0600 16 HPSERVER SMTP-OUT:00000001: >> RSET
01-17 00:26:51 -0600 16 HPSERVER SMTP-OUT:00000001: << 250 flushed
01-17 00:26:51 -0600 16 HPSERVER SMTP-OUT:00000001: >> QUIT
01-17 00:26:51 -0600 16 HPSERVER SMTP-OUT:00000001: << 221 Service Closing transmission
01-17 00:26:51 -0600 08 HPSERVER SMTP-OUT:00000001: Disconnected from 98.138.31.74
This behavior is not RFC compliant. Please note that we already have
a feature request in this sense and a RFC Break should be implemented
in Axigen. We suggest that you use another relay server, such as the one provided by your ISP.