If you are getting 1605 (Jet_errKeyDuplicate. illegal duplicate key, then most likely running eseutil /r will not help to resolve the issue. Eseutil /r switch replays the log files, which will not fix the issue in our case.
1605 is a bad error message and most of the time there is no way around from this error message. If you run the repair (eseutil /p)against this dtabase, most likely that will also give you 1605 again. (please check the article mentioned in the last post before even deciding running this. This might cause problem in future).
In this case the best thing will be to start with a fresh Information Store using Exmerge program. The following article tells how to does that :
Article number : q259688
XADM: How to Use the Exmerge Utility to Extract Data from a Damaged Database
The information in this article applies to:
Microsoft Exchange Server, version 5.5
This article describes how to use the Exmerge utility to extract user data from a Priv.edb database that has errors in it, such as error -1018 or error -1019, and then bring the data back into a new database on the same server.
The Exmerge utility is available in the Microsoft BackOffice Resource Kit.
You can only use the procedures in this article if the database is running. Remember that if there are errors in the database, some user data may be lost. Data loss depends on exactly where the errors are in the database. Also note that using the Exmerge utility results in loss the of single instance storage, which may result in a significant size increase in your database.
This section describes the steps for a Two-Step Exmerge process. This is the typical choice for administrators because it allows more more control during the process.
Run the Exmerge utility, and then click Next.
Click Two-Step Merge, and then click Next.
Click Step 1: Copy data to Personal Folders, and then click Next.
Type the server name for the Exchange Server computer that has the errors, and then click Options.
On the Data tab, verify that the User Messages and Folders, Associated Folder Messages, and Folder Permissions check boxes are selected.
Note that the Items From Dumpster check box is for recoverable items that have been deleted by users (when the Deleted Item Recovery option is enabled). This option requires more space on the destination partition.
On the Import Procedure tab, click the method that you want to use when you import the data from the .pst files. The Merge Data into the Target Store the option that is the most commonly used.
On the Dates tab, verify that all dates are selected.
Use all of the default settings on the other tabs, click OK, and then click Next.
The Exmerge utility connects to the information store and brings up all of the users that are in the directory for that server. Click Select All, verify that all the users are selected, and then click Next.
At the prompt that asks you where you want the .pst files stored, click a partition that has the necessary space for the .pst files. You can also point the .pst files to another server if you do not have space on the local drive. If this is the case, be sure to map a drive to the remote location. If you copy the .pst files to another server, the time that it takes to run the process increases substantially.
Click Next. The process begins to export your data to the .pst file.
After the export process is complete:
Stop the information store service, and then remove the Priv.edb database (you can move it to another server or rename it, but Microsoft recommends that you maintain a copy of your original database until you have determined that this process has worked correctly).
Start the information store service. This creates another Priv.edb database.
Log on to your mailbox and send a message to all of the users that on the server. This step is critical for the Exmerge utility process. To create the mailboxes in the Priv.edb database tables, you must either send a message to it, or you must open the mailbox.
Run the Exmerge utility again, and then click Next.
Click Two-Step Merge, and then click Step 2: Merge data from Personal Folders.
Type your server name, click Options, and then verify that the User Messages and Folders, Associated Folder Messages, and Folder Permissions check boxes are selected on the Data tab.
Leave all of the default setting on the other tabs, click OK, and then click Next.
All of the mailboxes from the server that you specified appear in the list. If they do not appear in the list, cancel out of the process, and then refer to step 3 because someone did not receive the initial message.
Click Select All, verify that all of the users are selected, and then click Next.
Point the directory to the location of the .pst files from step 1 of the migration, and then click Next to run the process.
After the Exmerge process is finished, your users may be asked the if they want the shortcuts to be changed when they log on after the data is brought back in. They should click Yes because the data has been brought back into a new Priv.edb database and all of the tables have been regenerated.
end of the article.