I am getting 421 status code errors below trying to do an email to text. Why is this happening? We have SPF, Reverse DNS, DMARC and DKIM verification in place.
Error Type: SMTP[nl] Remote server (18.104.22.168) issued an error.[nl] hMailServer sent: [nl] Remote server replied: 421 spr-ibgw-5001a.stratus.cloudmark.com cmsmtp SMTP server temporarily not available AUP#1260[nl]
Howdy cblaze22. A lot of times this type of error resolves it's self. So I see this was sent to us last night around 5pm. Are you still having this error?
Well why are your mail servers rejecting our emails? We are speaking to your cloudmark servers about this but thought this was a good place to ask also.
Are you sure you have the right company? What email are you trying to send to within Sprint?