Delayed Mail

[paulpr90]

Hi All,

We have SBS2003 running exchange fully service packed.

I have a problem with an email address that when we send to it after a while we get a message delayed problem. There doesn't appear to be a problem with recipient as when we use a web account or standard pop3 account the recipient recieves message fine. The problem on arises when we use exchange via outlook that this happens. Would any1 have any idea why or how to find out why.

Many Thanks Paul..

 

[TechCarnivore]

I had this problem and it turned out messages were just sitting in the SMTP queue. Can you validate the messages have left your exchange server?

 

[ShackDaddy]

Some mailservers use a relatively common spam-fighting tactic called "greylisting." I'm pretty sure that this is what you are encountering, especially since it's related to a specific email address.

The first time an unknown mail server sends mail to them. It essentially says: "I don't know you, and I'm not going to accept mail from you right now, but if you try again later, I'll accept it."

Most spamming servers never try again. There's not much you can do about it, but sometimes over time your server becomes "known" to the destination server and you aren't greylisted anymore. On the other hand, most of the time the behavior continues. For example, for the last three years, I get one of these messages every time I mail anyone at Hewlett Packard, but it is always eventually delivered. You just have to accept it.

ShackDaddy
Shackelford Consulting

 

[ShackDaddy]

As far as the difference in behavior between web client and Outlook on Exchange, there's no technical reason for this to be the case unless the "Outlook on Exchange" client is actually sending its mail out using an SMTP connection to an external server and not sending out via Exchange. Functionally, submitting a message via OWA and Outlook (MAPI) would be identical in the outbound and header characteristics.

ShackDaddy
Shackelford Consulting