Wednesday, October 10, 2012

Exchange PST Capture Tool: Import error: Error opening mailbox

Today a customer consulted me to import 600 mailboxes into Microsoft Exchange from PST files scattered across the network.  However when performing the import into Exchange the following error was experianced:

Import error: Error opening mailbox

Now this error ususally occurs when the user does not have Mailbox Import Export permissions. This can be assigned to a user using the following PowerShell command:

New-ManagementRoleAssignment -Role "Mailbox Import Export" -User "PSTImportUser"

However in my case this was not the problem.  I found out the hard way that you must have a 64bit version of Outlook installed on the PST Importer server.  My version of Outlook was 32bit hence causing the error.


  1. Does this mean that even if the PST file originates from a 32bit Outlook that a 64bit Outlook is needed on the PST importing machine? I am experiencing the same issues as you are.

  2. Hi Douglas, you just need to ensure the mailbox user on the Exchange server which your doing the importing from has Mailbox Import Export rights assigned to it with the command above.