Can't log into Outlook after MS update

David Wood 0 Reputation points
2026-09-15T12:54:34.5766667+00:00

Computer did an update. When I turned the computer on it asked if I'd like to see what's new with the update. I clicked Ok. It then automatically loaded all my files to the Cloud. Something I did not anticipate. I tried to open Outlook, but it could not find the pathway. It was empty of all data. I tried setting up the "new" Outlook, but it won't sync. I tried opening up the legacy Outlook and it had me create a password. Again, something I did not anticipate. At any rate, the legacy Outlook won't connect to my eMail provider any longer. All my files and saved eMails are lost and Outlook, new and legacy, are not connecting to my provider. I called the provider and found that I have the correct information, but MS Outlook will not recognize it, in spite of my using it for years.

PS Outlook is still working on my phone. Just having problems with the laptop since the most recent update.

[moderator's note: PII removed]

Outlook | Windows | New Outlook for Windows | For home
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  1. Vikki-T 10,395 Reputation points Microsoft External Staff Moderator
    2026-09-16T08:21:54.4066667+00:00

    Hi David Wood,

    I understand how concerning this is, especially when the update changed your Outlook setup and made your saved mail and files appear to be missing.

    At this point, I recommend that you review and try the steps provided in the AI generated answer on your thread. That reply typically include the most relevant checks for this scenario. 

    Since the mailbox still works on your phone, your server-stored emails are likely still available. Before deleting any Outlook folders, profiles, or data files, please sign in through your email provider’s webmail page and verify whether the missing messages are shown there. If they are, the issue is most likely limited to the Outlook configuration on the laptop.

    For Classic Outlook, please also check the status bar at the bottom of the window. If it shows Working Offline, select Send/Receive > Work Offline once to reconnect. You can then run Microsoft’s Classic Outlook connectivity troubleshooter, which checks common connection and authentication problems.

    If the account belongs to a third-party email provider, please confirm whether it is a POP, IMAP, or Exchange account and whether the provider now requires an app-specific password. You can compare the incoming and outgoing server details with the provider’s current settings.

    Regarding the missing locally saved mail, please do not remove the old Outlook profile yet. Some older messages may be stored only in a local .pst file. You can search the laptop for *.pst and make a backup copy before creating another Outlook profile or reinstalling Outlook.

    Could you also share:

    • The name of the email provider, without posting the full email address
    • Whether the missing emails appear in webmail
    • The exact error shown by Classic Outlook
    • Whether the files were moved into a OneDrive folder after the update

    These details will help determine whether this is an authentication issue, an incorrect server configuration, or a local Outlook data-file problem. Thank you so much for your understanding. 

    Note: Please follow the steps in our documentation to enable e-mail notifications if you want to receive the related email notification for this thread.

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  2. AI answer

    2026-09-15T12:54:56.63+00:00

    Since Outlook still works on the phone, the mailbox and provider settings are likely fine. The problem is on the laptop in Outlook after the update.

    Try this in order:

    1. Update Outlook first
      • Open Microsoft Store.
      • Go to Downloads and updates and select Get updates.
      • Restart Outlook and try adding the account again.
    2. Reset New Outlook local sign-in/cache data
      • Completely close Outlook.
      • Press Windows + R, enter %localappdata%\Microsoft, and press Enter.
      • Delete the Olk and OneAuth folders.
      • Start Outlook again and try to add the account.
      • This removes local Outlook state and cached authentication data so Outlook can rebuild it.
    3. If using New Outlook, add the account with manual IMAP settings
      • In New Outlook, go to Settings > Accounts > Email accounts > Add account.
      • Enter the email address and choose IMAP.
      • Select Show more and turn off Use recommended settings.
      • Enter the exact IMAP and SMTP server settings from the email provider.
      • If prompted to sync the IMAP account to Outlook, select Continue.
    4. If using Classic Outlook and it never prompts correctly for password
      • During IMAP setup, make sure Require logon using Secure Password Authentication (SPA) is unchecked.
      • If Outlook still does not prompt correctly, create the account again:
        1. Open Control Panel.
        2. Select Mail.
        3. Select Email Accounts.
        4. On the Email tab, select New.
        5. Enter the name, email address, and password, then complete setup.
    5. If Classic Outlook keeps asking for password or stopped working after a password change
      • Close Outlook.
      • Open Credential Manager from the Start menu.
      • Go to Manage your credentials > Windows Credentials.
      • Under Generic credentials, locate entries starting with MicrosoftOffice16_Data:OAUTH2.
      • Removing the affected cached OAuth credential can force Outlook to prompt for sign-in again.
      • After a password change, it can also take about one hour for the OAuth token to expire before Outlook prompts again.
    6. Verify the account settings in Classic Outlook
      • Open Control Panel > Mail > Email Accounts.
      • Select the affected account and choose Change.
      • Confirm the incoming and outgoing mail server settings match the provider.
      • Under Logon Information, confirm the full email address is used as the username and that the password is correct.
      • If the provider uses two-factor authentication, use the generated passcode instead of the normal password.
    7. If Outlook still cannot connect, create a new Outlook profile
      • Exit Outlook.
      • Open Control Panel > Mail.
      • Select Show Profiles > Add.
      • Create a new profile and add the email account.
      • Set Always use this profile to the new profile.
      • This is often the cleanest fix when an update leaves the Outlook profile in a bad state.

    About the missing mail and files:

    • The available guidance here covers reconnecting Outlook and resetting local Outlook state.
    • Deleting Olk and OneAuth only removes local Outlook cache/authentication data and Outlook recreates it.
    • If mail is still visible on the phone or in webmail, it is usually still on the mail server and can resync after the account reconnects.

    If the issue started because the laptop switched into New Outlook and Classic Outlook is preferred, reinstalling Classic Outlook may be necessary in some cases.

    References:

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

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