Hi,

We got an application sending out emails internally to our end users, it does so in bulks of about 50 or so. The application sends via a Exchange 2013 receive connector where the application server is listed as an allowed relay.

About 30% of the emails go through fine, but most are dropped in Exchange as such:

Timestamp SourceContext Source EventId

2/04/2015 13:02 ExplicitlyDiscarded SMTP HADISCARD

Its different recipients that get dropped every time and no other issues sending to any of these users.

• Edited by Trana010 Tuesday, April 07, 2015 2:20 AM

Hello

HADISCARD: A shadow message was discarded after the primary copy was delivered to the next hop.

so check smtp receive and send connector log for email what is missing.

Thanks, but the .\hub\protocollog\smtpreceive and smtpsend are both pretty much empty, nothing since months back in there.

The receive connector used is a HubTransport connector, so that would be the logs to search, correct?

Hello

on  the  receive connector enabled verbose logging?