Receive email from Exchange servers delayed.

[dandy34]

Our ISP recently moved to a new NOC and "somehow" our DNS records didn't get updated with the new DNS server information. In fact, they called me to let me know we might have a DNS problem. This caused the antennae to go up but we corrected the problem (I think). Our website and email is up and running for the most part. The strange thing is that when people using MS Exchange send us email it takes at least two days to arrive if it ever does. I've contacted a couple of sites that are trying to send us messages and had them flush their cache and it hasn't helped. Their emails get a "delayed delivery" when they try to send to us.
We're using Kolab for our MX and we host web and email on two different servers, each with it's own IP. I can ping the web server but the MX IP doesn't respond.
Our Registrar is NetworkSolutions and we have them pointing to the new ISP addresses. It's been a five days since the last change so I think it should have propagated by now.
Any help would be appreciated.

 

[Spirit]

Go striaght to;

http://www.dnsstuff.com

and

http://www.dnsreport.com

And have a look at your MX records.

Regards,

Iain

 

[dandy34]

Yep, the MX records look good, I do get email from other servers, just not Exchange servers. I've spoken with IT folks at the places that can't send and they've sent the the message headers on the bounced mails. I see that they're running Exchange 6 at least and as I've said I had one dump the DNS cache with no good results.

Thanks,

Sam

 

[Spirit]

I wonder if they've / you've only got like a SMTP connector and not a x.400 or x.500 compliant connector? And they don't support it or can't connect to it?

It's early and before my first coffee so struggling for thought pattern

I presumme you've rebuild you internet connector?

Iain.

P.S. I had this problem with a supplier years ago after changing my ip address. turn out their system had 6 load balanced servers and one server had a cached ip address which meant mail hitting server 1,2,3,4,5 worked fine but the mail to 6 got stuck in queues due to failed reverse look up.

 

[dandy34]

That's a possibility, I'll send your post to the guy I'm working with from the ISP and thanks for the info.

Sam