Just upgraded 2010. I'm slowly working the kinks out of the system. I'm getting a strange problem sending email with attachments. Some emails were rejected as noted below. The delay will eventually turn into rejection. The only thing unique about this email was that it included an attachment. I can send email to both of these recipients if it has no attachments. To test I sent the same email with the same attachment to a yahoo mail account I own. The email and attachment was promptly delivered. I checked my transport config and I have a 10MB limit on attachments, which this was well under. I don't know how to begin to track down a problem like that. Any suggestions? Delivery is delayed to these recipients or groups: xxx yyy Subject: FW: Release Notes for 9/14 This message hasn't been delivered yet. Delivery will continue to be attempted. The server will keep trying to deliver this message for the next 1 days, 19 hours and 57 minutes. You'll be notified if the message can't be delivered by that time.

Is your outbound mail directed through a smart host? Have you checked its configuration? Have you enabled protocol logging? If so, do you see anything of interest in there?Ed Crowley MVP "There are seldom good technological solutions to behavioral problems."

I have a single server installation; I don't think I have a smart host. I just turned on protocol logging, hopefully it will show something. There must be some setting I missed because mail to yahoo and google accounts is delieverd with attachments with no problem.

You can tell whether you have a smart host by looking at the properties of your send connector for the "*" (no quotes) address space.Ed Crowley MVP "There are seldom good technological solutions to behavioral problems."

D'OH....It looks like I must have a smart host.....the only address I have in my send connector is SMTP *...Now I have to research smart host.....where does one look at smart host configurations? Thanks.

One of the properties of the Send Connector is the smart host's name or IP address.Ed Crowley MVP "There are seldom good technological solutions to behavioral problems."

Even though the address is SEND ... * ... 1 on the Address Space tab I have no smart hosts configured on the Network tab. Could that be the problem?

Hi, you are sending to an external address, right? It seems to me it's an issue with the recepient, not yours, did you tried to send them emails with a very small attachment? what is the status of the emails with attachment in the queue? what is the last error? do the other side -the recipients- and you have a stable and good speed internet connection for the Exchange servers?

I'm thinking more and more it is not my problem. We have a subsidery company with a different email address right next door and I can't send them email with attachments...their system admin is working on the issue. Thanks.

Hi, you are sending to an external address, right? It seems to me it's an issue with the recepient, not yours, did you tried to send them emails with a very small attachment? what is the status of the emails with attachment in the queue? what is the last error? do the other side -the recipients- and you have a stable and good speed internet connection for the Exchange servers?

After spending two days on the phone with Microsoft support we discovered that the IgnoreStartTLS setting on my send connector needed to be set to true

Did they say why?Ed Crowley MVP "There are seldom good technological solutions to behavioral problems."