Hotmail SMTP error : 421 PR(dt1) Unfortunately, some messages from 75.126.28.xx weren’t sent.
Are you facing delivery problems on hotmail ? Getting 421 dt1 error and wonder why ?
Let me explain,this is a rate limitation put on your ip.Hotmail defers you possibly because of many reasons;
- Bad content
- No reads,no clicks
- Too many complaints received
- Bad SRD rate
- Too many emails sent in a very short period of time
- Last thing ; you are a spammer!
How to solve ? Detect your problem.Try to find out the reason and solve it.
Lower the volume to %20 of what you are sending,this should help.If you are not able to send even one single email,then contact microsoft and let ip rest for some time.