Exchange online 365 - Errors migrating and importing PST files to mailboxes RRS feed

  • Question

  • Hello there

    We are using the import PST file feature within the 365 Security and Compliance section to upload and import PST fails into users mailboxes of a recently created tenant. We have successfully uploaded the files to the Azure blob provided to us and have validated the CSV files for the import. But the import has failed twice now delivering complex log files as to why. Here is screen shot of the blob and contents from within Microsoft Azure Storage Manager:


    In the following example below, we are migrating PST files contained in the folder Staff02:

    We have tried a couple of times and receive mixed errors in the (complex) summary report like "MailboxAmbigous" , "these corrupted items will not be available at the destination mailbox" and "path=/psws; secure; HttpOnly" for each mailbox

    I'm not sure is we have PST import mapping wrong or a permission issue. One thing I note is that I cannot copy and paste a PST file outside it's folder directly into the blob with an error referring to permissions - don't know if that's related or not. Help here would be appreciated as I have clients waiting for their mail to populate!

    Thanks in advance


    Thursday, May 18, 2017 6:06 AM

All replies

  • Hi,

    How are things going now?

    The first thing I thought about is that these PST files are corrupted. Please try to import one of these files to one new on premise user mailbox to see if items are corrupted.

    If these PST files are corrupted, try to re-create these PST files.

    One more test, move user1.pst out from /staff02, put it on root default folder. In mapping file, empty the value of FilePath for user1. And try again to import this PST file.

    Best Regards,

    TechNet Community Support

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    • Proposed as answer by Lynn-Li Monday, June 5, 2017 1:39 AM
    Sunday, May 21, 2017 1:08 PM
  • While you are facing this problem you need to repair the PST file by using SCANPST.exe otherwise you can use the MailsDaddy PST to Office 365 Migration Tool for converting the PST file data like emails, contacts, calendars, appointments, and attachments etc into o365 Mailbox. For more about this application you can visit:

    Tuesday, January 15, 2019 11:01 AM