AOL Issue

[sipacino]

Hello all,

I would be most grateful for any advice anyone can give me for this problem I have.

One of my clients has a Microsoft Exchange Server (2000 with up to date service packs). One of the users on the domain sends to aol accounts regulalry. The exchange server refuses to send these mails. They just sit in the queue (retrying) until the default time out period expires at w3hich point the message comes back
"Could not deliver the message in the time limit specified. Please retry or contact your administrator."

Does anyone have any ideas? This only happens with mail sent to aol accounts.

Many thanks

Simon Evans
Systems Engineer

 

[Zelandakh]

In ESM, have a look at the emails and see what error they list. Often this is a DNS issue.

 

[PScottC]

AOL blocks email coming from many DSL IP ranges. You can contact AOL support and they will let you know if the external IP is in one of their blacklisted ranges.

Also, verify that you have a reverse DNS record on the internet. To find out just run nslookup <yourexternalIP>. If you get no record at all you will probably have to have one set up.

PSC

Governments and corporations need people like you and me. We are samurai. The keyboard cowboys. And all those other people out there who have no idea what's going on are the cattle. Mooo! --Mr. The Plague, from the movie "Hackers

 

[nhidalgo]

do an nslookup on their mailserver ips and try telneting to one on port 25 and see if you get an accessed denied banner.

Nick

 

[rliebsch]

http://www.dnsstuff.com/

is a great tool to use to check forward and lookups.

I had a similar issue with AOL about a month ago. Turns out there was an invalid reverse lookup. When the error was corrected, we lost contact with AOL for 3 days (and a few high clients as well) while the internal name caching servers retained the stale data...

I'd bet dimes to dollars you are having DNS issues. To test it, if you have an external mail server you can send from (in the same IP space), try sending it, AOL will likely tell you something to the effect of Domain does not exist, or errors in the 550s likely a 553: Domain of sender does not exist.

 

[sipacino]

Many thanks to you all for this advice. I am going to try the things you mention and will let you know the outcome.

Much appreciate the help!

Simon