Problem with reverse DNS

Hi All,

I have a problem with sending e-mail to a mail adres on, I get the following error:

Diagnostische data:

Server: DWV01EXCH02.DWV.local

rblsmtpd.local #553 We do not accept mail from IP addresses without reverse DNS. See ##

My DNS is:  A    1xx.2xx.156.4  MX  10  MX  90  

The mail go's to our hosted SPAM filter and from that it's send to our mail server. The e-mail get send out directly from our mail server. if I go to I get the following information:

Not an open relay.
0 seconds - Good on Connection time
9.173 seconds - Not good! on Transaction time
OK - resolves to
OK - Reverse DNS matches SMTP Banner

What am I doing wrong?
Who is Participating?

[Product update] Infrastructure Analysis Tool is now available with Business Accounts.Learn More

I wear a lot of hats...

"The solutions and answers provided on Experts Exchange have been extremely helpful to me over the last few years. I wear a lot of hats - Developer, Database Administrator, Help Desk, etc., so I know a lot of things but not a lot about one thing. Experts Exchange gives me answers from people who do know a lot about one thing, in a easy to use platform." -Todd S.

Check how to configure SMTP banner for Ex 2010

You will have to ask your ISP to set a PTR record to point to your IP - for


Experts Exchange Solution brought to you by

Your issues matter to us.

Facing a tech roadblock? Get the help and guidance you need from experienced professionals who care. Ask your question anytime, anywhere, with no hassle.

Start your 7-day free trial
JamesSenior Cloud Infrastructure EngineerCommented:
You need to setup a PTR record which points to your public ip. Your ISP provider should be able to set this up for you.
Go to site and enter you ip address for reverse dns. Basically you need to have your ISP set up the reverse dns records to resolve to the same domain you use sending mail. What is happening is that the recipient mail server is checking to see if the domains match from the email and the reverse lookup, before they accept your email.
Protecting & Securing Your Critical Data

Considering 93 percent of companies file for bankruptcy within 12 months of a disaster that blocked access to their data for 10 days or more, planning for the worst is just smart business. Learn how Acronis Backup integrates security at every stage

I used the tools here to get that fixed.

But yes, you need to be able to resolve back to your IP address.  
Definitely just call your ISP and get a reverse PTR.  They'll know exactly what to do.
xissAuthor Commented:
Thanks for the responses, we have multiple domain names on our exchange 2010 machine. and now our ISP tells me that we cannot have more PTR records than one?
That makes no sense. If you have registered domains you are currently using for email, then the ISP can add a PTR for each of them. The request to add reverse dns seems to be an issue for many ISP's, since the person you get to talk to does not know what to do. It typically takes us multiple trys to get an ISP to do it for our clients. I would call your ISP again, and tell them exactly what you want. Depending upon who your ISP is, and what type of service you have, you might be able to make these changes yourself using their online web based configuration, if such exists for your ISP.
xiss - who is your isp ?
JamesSenior Cloud Infrastructure EngineerCommented:
What you might need to do, is send a request by email to the support department of your ISP requesting PTR record be setup for domain name. This is what I had to do on a number of occassions.
JamesSenior Cloud Infrastructure EngineerCommented:
The other option is to forward mail through your ISP and that would resolve the issue with reverse dns.
xissAuthor Commented:
Thanks all for the responses! I have a private ISP in our datacenter he has now put a reverse DNS in his server and it works.
It's more than this solution.Get answers and train to solve all your tech problems - anytime, anywhere.Try it for free Edge Out The Competitionfor your dream job with proven skills and certifications.Get started today Stand Outas the employee with proven skills.Start learning today for free Move Your Career Forwardwith certification training in the latest technologies.Start your trial today

From novice to tech pro — start learning today.