Hi, We have an application which has a feature to recover emails. It worked fine with CGPro. Recently I migrated our mail system to Exchange 2007 and the feature stoped working. I tracked the message , and it shows DUPLICATEDELIVER for the email I want to reocvery. Then I changed two keys in Registry as follows: HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\MSExchangeIS\<Server Name>\<Private/Public-Guid>\Track Duplicates changed to 1 hour HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\MSExchangeIS\<Server Name>\<Private/Public-Guid>\Background Cleanup (in msecs). Changed to 60000 So I believe entires in DeliveryTO table will age out in an hour. So I waited for an hour and tried to recovery an email which was sent to me an hours ago, still doesn't work, neither does when try to recovery an email recievedfew days ago. I also tried to setup "keep deleted items" for 0 days on Exchange server, thendeleted someemails, then deletedthem from deleted items, wait for a few days, try to recover them, still not working, The tracked log still shows DUPLICATEDELIVER. Information Store has been restarted after I changed the registry. I suspected the DeliveryTO table not being updated properly? How can I know the DeliveryTO table has been updated or not? Thanks,

Hi, Can you explain more in detail which mail you are trying to recover? Let me explain a scenario, you received a mail in inbox and deleted it from deleted items too and you want to recover it In this situation by default Exchange 2007 will keep deleted item in dumpster for 14 days as per keep deleted items setting (so I would suggest you to set from 0 toto 14 days back). Now to recover it you need to enable a registry key DumpsterAlwaysOn on the workstation where you opened outlook, refer below article to recover deleted item. How to Recover a Deleted Item http://technet.microsoft.com/en-us/library/aa997155(EXCHG.80).aspx

Hi, Thank you for your replying. I'm trying to recovery any emails for example recieved last a few day through the application developed by our develepers who complained the application doesn't work after I migrated to Exchange 2007. I checked the tracking log, the Exchange server did see the message arrived but it looked it as a DUPLICATE so I believe the application developed by our software works fine. And I did some reasearch so that I got the above two registry keys setup up which doesn't seem work for me. How to verity the registry keey work or not? Setting "keep deleted items" to 0 just for this case testing. Thanks,

Hello, When you said your application server relay off Exchange 2007 to send mail, I got a click in my mind that have you configured your Exchange server for proper relay? By default it doesnt accept anonymous connections so you need to create a receive connector for application relay. Check this article... Allowing application servers to relay off Exchange Server 2007 http://msexchangeteam.com/archive/2006/12/28/432013.aspx

It doesn't fit for my scenario since I can see the message arrived at the Exchange server but for some reason it was a DUPLICATE email. Thats why I changed the two registry keys which not working for me.

I just did a few test. I can use our application to recover emails as old as 8 days before, however, while recoverying emails as old 7 days ago, I got DUPLICATEDELIVER event in the Message Tracking.

Hi, The current issue is youre using a self-developed software to recover mail, it worked with CGPro, but dont work with Exchange 2007. I think you should consult the developer of this software and find a workaround. You also can write a post on our develop forum to see if someone can help: http://forums.microsoft.com/TechNet/ShowForum.aspx?ForumID=838&SiteID=17 Thanks, Elvis

Hi Elvis, I doubt it is the self-developed software. What I have done: I can recover emails sent 8 days ago which means the DeliveredToTable got purged for those entries which are 7 (or 8) days agao. but I setup the registry key for Track Duplicates is setup to 1 which means 1 hour. 1.enabled the event log to medium for Background Cleanup 2, I can see from the event log Cleanup of the DeliveredTo table for database 'First Storage Group\Mailbox Database' was successful. 8886 entries were purged (out of 8921 entries visited). 3. created a second database in the same Storage Group 4. moved myself maibox to the new database 5. unmounted the new database and mounted back the database 6 waited for at least half a day and recieved a few eamils 7. checked in the event log: got Cleanup of the DeliveredTo table for database 'First Storage Group\test duplicate' was successful. 0 entries were purged (out of 0 entries visited). This is not right. This mens the DeliveredTo table has not entries but I did recieved quite a few emails 8.Tried to recover an email which sent two hours ago with our application, it didn't work. 9tried to recover an email which sent before moving my mailbox, it worked, which means during moving the mailbox, the DeliveredTo table got clean up. Please help!

Hello,Taoliu, did you ever get a satisfactory answer? We are having the exact same problem at my organization. We use MailScanner on a *nix box to scan email before routing it to the next server. When we were on Groupwise, and a quarantined email was released by MailScanner, it was delivered to the Groupwise mailbox. Since migrating to Exchange 2007, we too are getting the eventID "DUPLICATEDELIVER" when the released email is sent to the Exchange mailbox.I checked the server's registry settings and theTrack Duplicates key is set to 1 and Background Cleanup is set to 60000. Despite these settings, if an email is released by MailScanner >1 hour after the original message is quarantined, Exchange still sees it as a duplicate. Very frustrating!I have scoured Technet and the web and I have not found a solution. Anyone?Thanks!

Is there a configuration item available to modify the default "<=7 days, drop as duplicate" behavior (DUPLICATEDELIVER in Message Tracker) to "1 day"?