Lost saved emails after upgrading to Office 365

Martin Brown 0 Reputation points
2026-10-02T14:56:54.09+00:00

A couple of days ago, against my better judgement, I upgraded from Office 2024 HB to Office 365. During the process I lost all of my saved emails, some as old as 20 years that meant something to me. Since then, I have saved other emails, but when I open Outlook again, I have to saved emails in any of the files. I have a lot of saved files. Vacation booking information is gone, and I am really upset about this. Is there any way I can recover the emails?

Outlook | Windows | New Outlook for Windows | For home
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  1. AI answer

    2026-10-02T14:57:11.8733333+00:00

    Start with the places where Outlook commonly hides or restores missing mail:

    1. Check Outlook on the web first. If the messages appear there, the account still has the mail and the issue is likely with the Outlook app sync or profile.
    2. In Outlook, check Deleted Items, Junk Email, Archive, and any custom folders.
    3. If the messages are in Deleted Items or Junk Email, restore them:
      • In new Outlook, open Deleted Items or Junk Email.
      • Select the message(s).
      • Select Move, then choose Inbox or another folder.
      • For junk mail, messages can also be restored with Report > Not junk.
    4. If the messages are not in Deleted Items, use the recovery option from that folder if available. Items removed from Deleted Items are recoverable for 30 days in Outlook on the web or Outlook.com.
    5. If the missing mail was imported from a .pst file and then seems to disappear, Outlook may be hiding it. In classic Outlook, go to View > Change View and select IMAP Messages.
    6. If search is not finding older mail, in classic Outlook:
      • Go to File > Options > Search.
      • Enable Include messages from the Deleted items folder in each data file when searching in All Items.
      • Then go to File > Account Settings > Account Settings > Email > select the account > Change.
      • Move Download email for the past: to a longer period or All.
      • Restart Outlook.
    7. If recent mail is missing only from search results after a Windows update, rebuild the search index:
      • File > Options > Search > Indexing Options > Advanced > under Troubleshooting select Rebuild.
    8. If Outlook crashed and local saved mail was stored in Outlook data files, check whether the account is POP, IMAP, or Exchange:
      • With POP, mail may have been downloaded locally and removed from the server unless it was configured to keep mail on the server.
      • With IMAP or Exchange, check the server copy in webmail.
      • With Exchange, also check recoverable items through Deleted Items.

    If newly saved emails disappear every time Outlook is reopened, that points to a sync, profile, or local data-file issue rather than a one-time deletion. The most important immediate check is whether those emails exist in Outlook on the web. If they do not appear there and were only stored locally before the upgrade, recovery depends on whether the old Outlook data file still exists.

    References:

    AI-generated content may be incorrect. Read our transparency notes for more information.

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  2. Hendrix-V 19,745 Reputation points Microsoft External Staff Moderator
    2026-10-02T23:49:46.78+00:00

    Hi Martin Brown,

    Since the issue started immediately after moving to Microsoft 365 and newly saved messages are also not remaining available after restarting Outlook, it may be worth checking whether Outlook is currently using a different mailbox or data file than the one that contained your older messages.

    Please try these quick checks:

    1, Open Outlook and verify the email address shown in the top-right corner matches the account you previously used.

    2, Go to Settings > Accounts > Email accounts and check whether multiple accounts have been added.

    3, If you previously used Classic Outlook, search your PC for .pst files:

    • Open File Explorer
    • Search for *.pst
    • Note any large PST files (especially those created before the upgrade)

    4, If you find a PST file that appears to contain your historical mail, it may be possible to reconnect it using Classic Outlook and verify whether the messages are still stored there.

    If the missing emails are not visible in Outlook on the web and no PST files can be located, the next step would be to contact Microsoft Support directly so they can review the account configuration and determine whether any additional recovery options are available.

    Please note that this is a user-to-user support forum. Moderators, contributors including external Microsoft employees cannot directly intervene in Microsoft product features or access back-end systems. Our role is limited to providing technical guidance on reported issues, requests, or ideas.

    Let me know if you need further assistance, feel free to ask me by clicking "Add Comment" or "Add Answer" if you cannot add comment so your response will be visible. Thanks for your effort.

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