PTR records are enabled but other mail servers cannot send mail to the server.
If PTR verification is enabled, the server may be unable to receive mail from some domains because these domains do not have PTR records defined.
The following RFC provides useful guidance on which DNS entries should be created for
It is best practice to have PTR records defined for A records. An MX record contains an A record and therefore by deduction must have a PTR record associated with its A record.
The tools available at www.dnsreport.com and www.dnsstuff.com are useful in diagnosing such issues.
What is a DNS PTR record?: Article ME020206
How to set up PTR records under Microsoft's DNS Server: Article ME020115
When sending messages to Hotmail, they appear in the Junk Mail folder: Article ME020241
Unable to send email to some domains, such as Hotmail, Yahoo, etc.: Article ME020003
|Product:||MailEnable (All Versions)|
|Keywords:||PTR DNS MX A RFC records cannot send not receiving mail messages email|
|Class:||TIP: Product Tip|
|Revised:||Wednesday, May 4, 2016|