How To Resolve Unable To Manually Assign Owner To PST File Error PDD00007

When attempting to manually assign an owner to a PST file you get the following error:

"Assigned owner successfully to 0 PSTs, unable to assign to 1 PSTs"

The PSTEnterprise.log file shows the following error when attempting to assign the owner:

2017-08-01 14:38:45.1085  27:  AssignMailbox assigning determined mailbox 'Surname, Firstname' to PST 'c:\archive.pst'
2017-08-01 14:38:45.1085  27:  Trace     : -> Started call [PSTDataDiscovery.CreateMailboxRowFromCommonPSTFile(session)]
2017-08-01 14:38:45.1085  27:   INFO      :PSTDataDiscovery:CreateMailboxRowFromCommonPSTFile() - searching for existing row using SMTP 'user@barracuda.com' and DN '/o=cuda/ou=external (fydibohf25spdlt)/cn=recipients/cn=user1234'
2017-08-01 14:38:45.1085  27:  PSTDataDiscovery, Error Code:PDD00007 ,CreateMailboxRowFromCommonPSTFile found 2 rows in PSTMailbox for mailbox '/o=cuda/ou=external (fydibohf25spdlt)/cn=recipients/cn=user1234'
2017-08-01 14:38:45.1085  27:  Trace     : <- Completed call [PSTDataDiscovery.CreateMailboxRowFromCommonPSTFile(session)]
2017-08-01 14:38:45.1085  27:  AssignMailboxCommon failed to create the mailbox row, failing assignment

The owner assignment fails are there two entries for the owner's mailbox in the SQL database. This could occur if the mailbox has been migrated from on-premises to Office 365 and thus its mailbox DN has changed but the SMTP address is the same. In earlier product versions, this may have resulted in multiple entries in the table for the same mailbox.

To resolve the issue:

1. In SQL Management Studio, connect to the PST Enterprise SQL instance.
2. Run the following query:
   SELECT [ID], [SMTPEmailAddress], [MailboxDN] FROM [PSTMailbox] WHERE [SMTPEmailAddress]=''
   where is the SMTP address of the user in question (e.g. in the above logging example user@barracuda.com)
3. The select statement returns two rows, for example:
   [ID]=3, [SMTPEmailAddress]= user@barracuda.com, [MailboxDN]=/o=myserver/ou=Exchange Administrative...
   [ID]=7, [SMTPEmailAddress]= user@barracuda.com, [MailboxDN]=/o=ExchangeLabs...
   In this example, ID=3 is the old on-premises mailbox DN and ID=7 is the new mailbox DN once the mailbox was migrated to Office 365.
4. Any PSTs assigned to the old on-premises mailbox DN (not containing ExchangeLabs), need to be reassigned to the new mailbox DN (containing ExchangeLabs). Run an UPDATE statement to replace the old ID with the new ID:
   UPDATE [PSTFile] SET [PSTMailbox_id]=<Old_ID> WHERE [PSTMailbox_id]=
   where is the ID for the old on-premises mailbox DN and is the ID for the 365 mailbox DN
   In the previous example, ID=3 is the old mailbox DN and needs to be replaced by the new mailbox DN which is ID=7, so the statement would be: UPDATE [PSTFile] SET [PSTMailbox_id]=7 WHERE [PSTMailbox_id]=3
5. Now delete the entry for the old on-premises mailbox DN from the table:
   DELETE FROM [PSTMailbox] WHERE [ID]=<Old_ID>
   where is the ID for the old on-premises mailbox DN
   In the previous example, ID=3 is the old mailbox DN, so the statement would be: DELETE FROM [PSTMailbox] WHERE [ID]=3

You can now assign the PST file manually to the correct mailbox through the PST Enterprise administration website.