gmail sync issue

James Wells 0 Reputation points
2026-09-03T14:18:41.7066667+00:00

gmail account on classic outlook is no longer syncing. It is stuck synchronizing folders and cannot send mail.

Microsoft 365 and Office | Other
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  1. John Jefferson Doyon 85,525 Reputation points Independent Advisor
    2026-09-03T15:06:09.8566667+00:00

    Hi,

    If you haven't already, you can try the "Manual Workaround" provided in this Microsoft article:

    https://support.microsoft.com/office/unable-to-add-a-gmail-account-to-classic-outlook-4d9530c5-3f40-4e6d-9b45-4477f160828f

    Please scroll down and follow the steps under the "Manual Workaround" section and then restart Outlook after completing them.

    Let me know if you have any further questions or concerns.

    Click "Add comment" to let me know.

    Thanks!

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  2. AI answer

    2026-09-03T14:18:56.53+00:00

    This matches a known classic Outlook issue affecting some Gmail accounts.

    If the problem started around late February 2026, Microsoft fixed the service-side issue on 3/20/26. If a Gmail password was changed, Outlook may still not prompt for sign-in until the OAuth token expires, which usually takes about one hour. To force Outlook to prompt for sign-in sooner:

    1. Close Outlook.
    2. Open Credential Manager from the Windows Start menu.
    3. Select Windows Credentials.
    4. Under Generic credentials, find entries starting with MicrosoftOffice16_Data:OAUTH2.
    5. Expand them and identify the ones that include tp_google_imap_Oauth2.
    6. Remove each matching MicrosoftOffice16_Data:OAUTH2 credential for the Gmail account.
    7. Restart Outlook and sign in to the Gmail account again.
    8. If mail does not start syncing immediately, restart Outlook one more time.

    If that does not fix it, the next workaround is to remove the Outlook identity entry for that Gmail account.

    Warning: editing the registry can cause system or profile issues if the wrong key is deleted.

    1. Close Outlook.
    2. Right-click Start > Run, type regedit, and select OK.
    3. Go to: Computer\HKEY_CURRENT_USER\Software\Microsoft\Office\16.0\Common\Identity\Identities
    4. Under Identities, select each subkey until the Gmail address that is not syncing is found.
    5. Delete only the identity key for that affected Gmail account.
    6. Restart Outlook and sign in again.

    If the issue happens while adding the Gmail account or after re-adding it, make sure the Google sign-in consent includes: “Read, compose, send, and permanently delete all your email from Gmail.”

    If Outlook is on Current Channel Version 2412 Build 18324.20168 or later, use the Retry link on the error window to repeat the browser sign-in and grant that permission.

    Also check these basics:

    • Make sure the internet connection is working.
    • If a password was recently changed, Outlook may need to prompt again after token expiry.
    • If a message is stuck in Outbox with an attachment larger than 20 MB, remove the attachment or send a smaller file.
    AI-generated content may be incorrect. Read our transparency notes for more information.

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