Problema invio mail con comando BDAT

Offending Line:

2016-05-17 13:12:32 66.110.xx.xxx OutboundConnectionCommand MAILSVR01 - 25 BDAT 43574+LAST 0 0 4 0 16 SMTP - -

So the solution was to disable BDAT, BINARYMIME and CHUNKING on the local SMTP Server.

Telnet to the mail host and issue the ehlo command.  Check the verbs the server returns.  It should have BINARYMIME and CHUNKING listed.  After these steps you will not have these.  

Verify BINARYMIME and CHUNKING are turned on.:
telnet localhost 25

Type ehlo

220 MAILSVR Microsoft ESMTP MAIL Service, Version: 7.5.76
01.17514 ready at  Tue, 14 Mar 2017 12:18:50 -0400
ehlo
250-MAILSVR Hello [168.1.1.1]
250-TURN
250-SIZE 51200000
250-ETRN
250-PIPELINING
250-DSN
250-ENHANCEDSTATUSCODES
250-BINARYMIME
250-CHUNKING
250-8bitmime
250-VRFY
250-TLS
250-STARTTLS
250 OK

Install IIS6.0 Resource Kit 

Open IIS Metabase Explorer

Navigate to LM\SmtpSvc\1

Look for SmtpInboundCommandSupportOptions

Here the default value was 7697601.  I knew that I wanted to disable the BINARYMIME and CHUNKING verbs so using the table here I subtracted 2097152 (BINARYMIME) and 1048576 (CHUNKING) from 7697601:

7697601 - (2097152 + 1048576) = 4551873

Set the SmtpInboundCommandSupportOptions value to 4551873

Disable BDAT

Navigate to LM\SmtpSvc

Change value of SmtpOutboundCommandSupportOptions from 7 to 5

Close the IIS Metabase Explorer and restarted the IIS Admin Service (which in turn restarts the Simple Mail Transfer Protocol (SMTP) service).  

Repeat the steps to connect to the server via telnet and verify they have been removed.  If they have not make sure you are in the \1 subdirectory when you make the changes.