We are trying to allow people to send emails to us with attachments over 10MB, but when I check the Message Tracking Center, I see the email come through and generate an NDR.SMTP: Message Submitted to Advanced QueuingSMTP: Started Message Submission to Advanced QueueSMTP: Message Submitted to CategorizerSMTP: Message Categorized and Queued for RoutingSMTP: Non-Delivered Report (NDR) GeneratedI've set No Limit on the Receiving Message Size under Global Settings / Message Delivery.On our SMTP Virtual Server, the Limit message size is Unchecked.Do I have to restart the server or some service for the changes to take effect? Or did I miss something?

Check everything here: ( Note that the GLOBAL send and receive limits have to be the same as the lowest limt will apply!)http://support.microsoft.com/kb/322679How to set size limits for messages in Exchange ServerIf everything looks correct as far as limits, then yes, restart the Exchange SMTP and Routing Services and then retest.

Looks like the problem was that the Limit message sized was unchecked. Once I checked that and entered a size, the emails came through.