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Remote SMTP Server Returned: 554 PTR for unauthenticated connections.

M

martinbl

Guest
Hi,

every once in a while, when I try to send email to people, I get this error msg:
Recipient: [SMTP:[email protected]]
Reason: Remote SMTP Server Returned: 554 This server requires PTR for unauthenticated connections.

So I did some googling and found I need to have reverse DNS for the smpt server I use.

I use the smtp in plesk and I have multiple domain on the same IP.

So how can I have every smtp have a reverse DNS (PTR) record?

And how can I avoid such error message?
Thanks
 
We are having the same issue, you see it is not enough to set a PTR record for each domain on the server, as this will not allow you to send mail to some very big ISP's like AOL, MSN and Verizon.

So we decided that we would remove the induvidual PRT records from each domain and keep a main PTR record for the server on the main/defualt domain for the server which is own own domain.

However, we are now getting the same error as you:
This server requires PTR for unauthenticated connections!

So what do we do now? Seems like either way we are up the creek without a paddle. Anyone got any suggestions?
 
I wrote to tech support. Hopefully, I'll get an answer soon.
 
It is strange becuase when I look at the MailEnable Diagnostic util, it shows that the outbound SMTP interface is an IP that is not the main shared IP of the server, and thus fails the reverse lookup, does anyone know how to designate the IP binding for outbound SMTP email on MailEnable? This may fix the issue, if it is possible.
 
Ah I think I might see where the problem is, I have two seperate ranges of IPs on this server, one IP range is 69.90.244.0/24 which has been added to the server to provide vhosts with dedicated/exclusive IPs for SSL and the other is 64.34.130.0/24 which is used for shared IPs. The main shared IP of the server which has the bulk of the domains running over it is within the 64.34.130.0/24 range but MailEnable is binding one of the exclusive IPs 69.90.244.0/24 to outgoing email. Thus even though the exclusive IP in the 69.90.244.0/24 range does in fact have a PTR record when someone tries to send email using the main shared IP which is in the other IP range, the PTR fails since is only checks the 69.90.244.0/24 range. I am also going to post this on the MailEnable site forum.
 
Hello people,

Was this ever solved ? The main question remains: what value must I set a reverse dns record entry to so that it will work for all outgoing mail from my Plesk sever, regardless from what domain on that server it comes from...

Really like to know !

Regards,

Mav.
 
how sad

wow, has anyone ever gotten a response from anyone????
 
We are having the same issue , we need a solution pls check,

Thank you.
 
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