Unfortunately still not having luck here. In the following location on our lone Exchange 2013 server's registry, we have two private keys:
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\MSExchangeIS\Server\Private-<GUID> Under both keys, I've added the following DWORD entries: Background Cleanup - decimal value = 60000 DeliveredTo Expiration in Hours - decimal value = 1 Track Duplicates - decimal value = 1 [cid:[email protected]] I've restarted the MSExchangeIS service (and rebooted the server overnight), and we still are not able to receive redelivered messages newer than 7 days old. Anything prior to that is redelivered successfully. What am I missing? From: Daniel Carp Sent: Tuesday, May 12, 2015 2:37 PM To: '[email protected]' Subject: RE: Delivery of same message multiple times Thank you, Jim - I've added Track Duplicates (with value of 1) and Background Cleanup (with value of 60000). I can't restart Exchange IS until off hours tonight, but I'll test tomorrow. Looks like this should do it, though. Appreciate you pointing me in the right direction! Best, Dan From: [email protected]<mailto:[email protected]> [mailto:[email protected]] On Behalf Of Kennedy, Jim Sent: Tuesday, May 12, 2015 1:20 PM To: '[email protected]' Subject: [Exchange] RE: Delivery of same message multiple times There is a duplicate message detection time period. So if two come in with the same ID within the time frame it considers it a dupe and drops the message. You can configure the time limit in the registry. http://msexchangeguru.com/2013/04/22/transport/ https://technet.microsoft.com/en-us/library/dd577073(v=exchg.80).aspx From: [email protected]<mailto:[email protected]> [mailto:[email protected]] On Behalf Of Daniel Carp Sent: Tuesday, May 12, 2015 12:43 PM To: '[email protected]' Subject: [Exchange] Delivery of same message multiple times We are using Google Apps' spam filtering service. All mail flows through Google's servers then approved messages are passed along to our Exchange 2013 (CU8) server. Google maintains lists of all messages that were approved, and from this list, individual users have the option to "Send again" for any given message. Until recently, I could have sworn that clicking "Send again" made a new copy of the message appear in the user's Inbox. However now clicking "Send again" seems to do nothing that the user can see. When I check Exchange's delivery reports, there are unique entries for the original message delivery and each subsequent request. The content of the delivery reports are identical other than the "Sent" time. Is there a setting somewhere that might prevent Exchange from delivering multiple messages with the same message ID? Any other thought on what could be the cause? Thanks in advance! Best, Dan
