Cannot send email to any BT email addresses

[JGOUGH]

Hi,

I have a customer (non BT) that has their own internal email server running Exchange 2010 and for some reason they are unable to send email to any BT email addresses, all other external email sends without issue. I can only assume that it is being blocked at BT by either domain name or ip address. I cannot find anyone at the BT end to talk to with referance to this. So any help would be gratfully recieved.

Regards

J

[Stephenc]

Hi J,

There's a few things that could cause this, has reverse dns been setup?

The domain may still be on one of BT's systems causing mail routing issues (we can remove this).

Your ip address could be blacklisted, do you get an error?

Thanks,

Steve

[JGOUGH]

Hi Steve,

I can send you the domain in question so that you can check this, let me know where to send it to, I would rather not post it in the forum.

Also I am not sure about the reverse DNS and so I guess not, do you have any info on how we would go about setting this up?.

The only error we go is one of there being a delay in sending the mails and we know that they never actually get there.

Thanks for your prompt reply, please let me know what steps to take next.

Regards,

Jason

[Stephenc]

Hi Jason,

If you click on my name then click, send this user a private message, I'll check the domain and your reverse dns status.

Do you run your mail server on a BT business line?  Or a 3rd party?

Thanks,

Steve

[JGOUGH]

Hi Stephen,

Sorry to hassle but I am just wondering what you have found?.

Jason

[DaveA]

Hi Jason,

Steve just PM'd me to let you know to check your PMs about this, as he sent you some info.  He's not able to post on the forums for a few days unfortunately.

Dave

[JGOUGH]

Hi Dave,

I have not recieved any info can you get it over to me please?.

Jason

[DaveA]

Hi,

As it was sent by PMs I can't do anything with it, but Steve did manage to drop me a message to say that you need to get reverse DNS set up by your domain host, as the domain isn't with us.

That should help unless there's some form of active blacklist in place.

Dave

[JGOUGH]

Hi Dave,

I have run some more tests and I dont think that the reverse dns will help in this instance as if I telnet to the BT mail servers, I get this in the response:-

Receiving "421 4.7.1 [TS03] All messages from x.x.x.x permanently deferred" when sending email to Yahoo!

So it seems that we are being blocked, how do I go about getting us removed from the block?.

Jason

[DaveA]

Hi Jason,

It would be up to Yahoo at that point, as they'd have to remove the block.

Dave