Unable to connect to Gmail account from outlook client

Question

Recently, a gmail account which has been working fine suddenly stopped syncing.

I deleted the gmail account and tried to add it back in, no I'm getting a message "We wern't able to set up your Google account with IMAP. You may need to make changes to your Gmail settings.

I checked the Gmail settings and they all look fine - IMAP is enabled.

This was working previously and there were no changes made to Outlook or Gmail configurations.

I'm able to connect to other gmail accounts from outlook and I'm able to connect other email clients to the same gmail account that fails on Outlook (e.g. K9 mobile email app). It looks like there is something unique about the combination of Outlook and this specific email account.

Answer 1

Hi Gary O’Neall, 

I hope you are doing well ! I just want to check if you have had a chance to test the steps earlier? Please let me know if they helped resolve the issue or if you are still experiencing any difficulties. I am here to assist you further.

Best Regards

Answer 2

This is far too complicated for me. Is there someone I can share screen with who will complete this process. I'm afraid to mess up all my other emails. I will pay someone to fix this for me. I can no longer run my business efficiently because my main email just stopped syncing. This is a complete disaster. Does anyone know of another email client that works well with gmail? If I can't fix this I am going to have to abandon Outlook, which would be another major inconvenience...

Answer 3

Dear Gary O’Neall, 

Thank you for reaching out to the Microsoft Q&A forum. I understand one specific Gmail account that previously worked in classic Outlook suddenly stopped syncing, and when you try to add it back you receive: “We weren’t able to set up your Google account with IMAP…”. I am happy to assist you. Have you tried the AI given steps yet? Please:  

1. Make sure classic Outlook is on the build that contains the fix, then retry the sign-in. After updating to a fixed build, re-add the Gmail account and use the Retry link on the error window to repeat the browser sign-in, making sure the consent box for Microsoft apps & services (“Read, compose, send, and permanently delete all your email from Gmail”) is selected.  If you are seeing the same error at add-account time, open another browser window (available in Version 2404 Build 17531.10000 and later, depending on channel).  
2. If you are already on a fixed build and it still fails, clear the stale Google consent + cached OAuth tokens for just this Gmail account. Close Outlook, then sign in to the affected Google account and remove “Microsoft apps & services” access (Google Account > Security > Your connections to third-party apps & services > Microsoft apps & services > Remove all access). Then open Windows Credential Manager and remove the Gmail IMAP OAuth credentials that start with “MicrosoftOffice16_Data:OAUTH2” and include “tp_google_imap_Oauth2” (there are two per Gmail account). If you need to avoid removing credentials for other Gmail accounts, map the correct identity using this registry path:  Computer\HKEY_CURRENT_USER\Software\Microsoft\Office\16.0\Common\Identity\Identities. After clearing consent and credentials, open Outlook and sign in via browser again (or add the Gmail account back) and ensure the Gmail permission checkbox is selected during browser sign-in.  

Thank you for your understanding, please let me know when you have further updates. I am here to help.

Look forward to hearing from you.

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Answer 4

Use the Outlook/Gmail-specific fixes for classic Outlook rather than changing generic IMAP settings, since other Gmail accounts work and IMAP is already enabled.

1. Confirm Outlook build has the Gmail fix
   • The error text matches the known issue: “We weren’t able to set up your Google account with IMAP. You may need to make changes to your Gmail settings.”
   • This is fixed in classic Outlook starting with Current Channel Version 2412 Build 18324.20168.
   • Update Microsoft 365 Apps, then retry adding the account. For build details, see About Office: What version of Office am I using? (linked from the article).
2. Use the Retry sign-in flow (if on the fixed build)
   • Add the Gmail account again in classic Outlook.
   • When the error appears, use the Retry link in the error window.
   • In the browser sign-in page for Google, ensure the box is checked for:
     • “Read, compose, send, and permanently delete all your email from Gmail.” under Microsoft apps & services can access.
   • Complete the sign-in and allow access.
3. If Retry does not work, use the manual workaround for this one Gmail account Step 1 – Remove Microsoft apps & services access in this Gmail account
   1. Close Outlook.
   2. Sign in to the problematic Google account at Google.com.
   3. Select the profile picture → Manage your Google Account.
   4. Go to Security.
   5. Under Your connections to third-party apps & services, select Microsoft apps & services.
   6. Under Microsoft apps & services has some access to your Google Account, select See details.
   7. Under Access you've given to Microsoft apps & services, choose Remove all access, then Confirm.
   Step 2 – Remove the cached Google IMAP OAuth credentials for this account
   1. Open Credential Manager from the Windows Start menu (in some Windows 10 setups, open Control Panel first, then Credential Manager).
   2. Select Windows Credentials.
   3. Under Generic Credentials, find entries starting with MicrosoftOffice16_Data:OAUTH2.
   4. Expand each and hover over the name until the full name including tp_google_imap_Oauth2 is visible – these are the Gmail OAuth credentials.
   5. Remove both credentials for this Gmail account (there are two per Gmail account).
      • If multiple Gmail accounts exist and only this one should be cleared, map credentials using the registry key:
        • Computer\HKEY_CURRENT_USER\Software\Microsoft\Office\16.0\Common\Identity\Identities
        • Match the identity subkey number to the corresponding credential entry, then remove only those.
   Step 3 – Re-add/sign in to the Gmail account from Outlook
   • Reopen Outlook.
   • If the account is still present but not syncing, use the Sign in via browser banner and sign in again, ensuring the Microsoft apps & services permission box is checked.
   • If the account was removed, use File → Add account, add the Gmail address, and complete the browser sign-in, again checking the permission box.
4. If Outlook still shows the same IMAP error
   • Verify again that IMAP is enabled in this Gmail account’s settings (Google is gradually removing the toggle for some users, but where present it must be enabled). For details, see Google’s “Add Gmail to another email client” article (linked from the Outlook support article).
   • If other Gmail accounts continue to work in the same Outlook profile after these steps, the issue is typically resolved once the cached OAuth tokens and the old Microsoft apps & services grant are fully cleared and re-established.

If the environment is Outlook.com (web) with a connected Gmail account rather than Outlook for Windows, note that Outlook.com no longer supports adding new third‑party connected accounts like Gmail; in that case, use Outlook for Windows or another supported method instead.

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References:

• Unable to add a Gmail account to classic Outlook
• Unable to sign in or add a Gmail account to classic Outlook
• Unable to add a Gmail account to Outlook "Could not sign you in to Google"
• Fix problems connecting your Google account to the Microsoft Cloud
• Connected email accounts like Gmail and Yahoo not working in Outlook.com