Issue adding email account to Outlook

Question

I had issues with send/receive with my [Moderator note: Removed PII]@gmail.com so I removed the account hoping this could of fixed the problem. Now I'm having trouble adding it back to Outlook

Answer 1

Hello Mary Abouatallah

Please note that our forum is a public platform, and we will modify your question to hide your personal information in the description. Kindly ensure that you hide any personal or organizational information the next time you post an error or other details to protect personal data.

Thank you for sharing the details. Based on your description, this usually happens when Outlook still keeps old Google (OAuth) sign‑in data after an account is removed. When that cached authorization becomes corrupted, Outlook may fail to add the Gmail account back.

To avoid repeating the Q&A Assist reply under your post, could you tell me if you’ve tried those steps yet, and what happens when you try?

Also, Microsoft has acknowledged a recent issue affecting some Gmail and Yahoo accounts in classic Outlook, including error 0x800CCC0E, and the issue is still under investigation. You can refer to the official workaround here: Users get errors 0x800CCC0E & 0x800CCC0F synchronizing Gmail and Yahoo accounts in classic Outlook - Microsoft Support

In addition, please try the following:

Step 1: Remove Outlook access from your Google account

1. Close Outlook.
2. Sign in to your Gmail account at https://www.google.com (Disclaimer: This is links to third‑party website. This site is not controlled by Microsoft, and Microsoft is not responsible for their content or any changes made by the third party)
3. Select your profile picture > “Manage your Google Account”.
4. Go to “Security”.
5. Under “Your connections to third‑party apps & services”, select “Microsoft apps & services”.
6. Choose “Remove all access”, then confirm.

Step 2: Clear Gmail OAuth credentials in Windows

1. From the Windows Start menu, search for “Credential Manager” and open it.
2. Select “Windows Credentials”.
3. Under “Generic Credentials”, locate entries starting with “MicrosoftOffice16_Data:OAUTH2” (these are Gmail OAuth tokens).
4. Remove all entries related to Gmail (there are usually two per account).

Note: These steps only remove local sign‑in tokens and do not delete your email data.

Step 3: Add the Gmail account again

1. Open Outlook.
2. Go to File > “Add Account”.
3. Enter your Gmail address and continue.
4. When the browser window opens, sign in to Google and make sure Microsoft apps & services are allowed.
5. Let Outlook finish setting up the account.

Please feel free to let me know how it goes after trying these steps. Thank you for your time and understanding.

---

If the answer is helpful, please click "Accept Answer" and kindly upvote it. If you have extra questions about this answer, please click "Comment".    

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.

Answer 2

Follow these steps to get the Gmail account working again in classic Outlook for Windows.

1. Remove old access and cached credentials

Because the account was removed and re‑added, Outlook may still be holding broken Google/OAuth credentials. Use the documented manual workaround:

Step 1 – Remove Microsoft Apps & Services access in Gmail

1. Close Outlook.
2. Sign in to the Gmail account at google.com.
3. Select the profile picture (top-right) > Manage your Google Account.
4. In the left menu, select Security.
5. Scroll to Your connections to third-party apps & services and 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, select Remove all access.
8. Select Confirm.

Step 2 – Delete the Google IMAP credentials from Windows Credential Manager

1. From the Windows Start menu, search for Credential Manager and open it (on Windows 10, open via Control Panel if needed).
2. Under Manage your credentials, select Windows Credentials.
3. In Generic Credentials, find entries starting with MicrosoftOffice16_Data:OAUTH2.
4. Expand each and hover over the name until it shows the full value including tp_google_imap_Oauth2 – these are the Gmail credentials.
5. Select Remove for each credential with MicrosoftOffice16_Data:OAUTH2 (there are two per Gmail account).

Optional (to target only this Gmail account):

• Open Registry Editor and go to: Computer\HKEY_CURRENT_USER\Software\Microsoft\Office\16.0\Common\Identity\Identities
• Use the identity subkeys to map which Credential Manager entries belong to this Gmail account, then remove only those.

2. Add the Gmail account back into classic Outlook

1. Open Outlook.
2. Go to File > Add account.
3. Enter the Gmail address (******@gmail.com) and continue.
4. When the browser sign-in window opens, sign in to Google.
5. On the Google permissions page, make sure the checkbox for Microsoft apps & services is selected/allowed.
6. Complete the sign-in and let Outlook finish configuring the account.

If the account had been removed from the profile earlier, this process will add it back cleanly with fresh OAuth credentials and restored access.

---

References:

• Unable to add a Gmail account to classic Outlook