Line 382453: 16:47:05 [220.127.116.11] cmd: RSET
Line 382454: 16:47:05 [18.104.22.168] rsp: 421 Too many bad commands, closing transmission channel
is coming from the RECIPIENT'S MAIL SERVER and is not a SmarterMail issue.
The receiving mail server has decided to throttle how many messages you can send in a given day.
If you do not have DomainKeys, DKIM, SPF, rDNS and DMARC setup, along with proper FEEDBACK LOOPS., you WILL be throttled now.
This is very clearly stated in YAHOO!, GMAIL. OUTLOOK.COM (which now handles all of the Microsoft e-mail services), and about 15 other ISPs.
They will also need POSTMASTER and ABUSE aliases or accounts setup: These should point to a valid, WORKING e-mail address that YOU, as the SmarterMail server operator, respond to, and will be used to setup your FEEDBACK LOOPS.
Finally, setup DMARC and USE IT. It will prevent you from being JOE-JOBBED and that will prevent you from becoming listed on BACKSCATTER.ORG
E-Mail is no longer set it and forget it. It requires a lot of work to setup each domain (and control panels do not do a good job of setting it up) and also requires a lot of day-to-day maintenance work.
SmarterMail makes the job a lot easier, but only if you take the time to properly setup the hosted domains, all of the associated records, and make certain they are all in compliance and STAY in compliance.
Remember, all records in a list MUST now be DOUBLE OPT-IN CONFIRMED and, if they bounce, or request removal, must be removed in THREE OR FEWER BUSINESS DAYS.
Remember, too, that when someone requests removal you MUST remove them and are not allowed to ask why.
Phonr: (773) 491-9019
Phone: (224) 444-0169
E-Mail and DNS Security Specialist
Network Security Specialist
Customer Service Portal: https://portal.chicagonettech.com
Security Blog: http://networkbastion.blogspot.com/
Web and E-Mail Hosting, E-Mail Security and Consulting