I've upgraded our 2013 server to CU9 and have enabled MessageCopyForSentAsEnabled and MessageCopyForSendOnBehalfEnabled. Now I see the following warnings in the application log of the Exchange server

MSExchange Extensibility
1051

Agent 'Shared Mailbox Sent Item Agent' caused an unhandled exception 'SmtpResponseException: 250 2.1.5 SharedMailboxSentItemsAgent; Sent item copy to shared mailbox successfully.' while handling event 'OnPromotedMessage'

All works well, can I ignore this message?

Thnx Remco

• Edited by Remco Tiel 21 hours 13 minutes ago

Hi Remco...

Error 1051 implies that there is a problem in the transport agent while handling the SMTP agent....

Check out this technet blog to find the resolution...

https://www.microsoft.com/technet/support/ee/transform.aspx?ProdName=Exchange&ProdVer=8.0&EvtID=1051&EvtSrc=MSExchange+Extensibility

Hope this will work.

Hello Henry,

Thnx for the reply, I already saw this article. It has something to do with the new functionality in CU9, we don't use third party agents. All works well but I don't like warnings in the application log and I think more people will address this issue when they activate this feature.

Remco

Same issue here, just noticed the warning too. Sent items do appear in the shared mailbox sent items though.