Unable to add a Gmail account to classic Outlook

Last Updated: October 17, 2024

ISSUE

When you try to add a Gmail account to classic Outlook you may see the error:

“We couldn’t log on to the incoming (POP/IMAP) server. Please check your email address and password and try again.”

Something went wrong Gmail error in Outlook

If you have an existing Gmail account in your Outlook profile you may see the following error when trying to Send/Receive:

“Task: ‘Synchronizing subscribed folders for username@gmail.com.’ reported error (0x800CCC0E): ‘Outlook cannot synchronize subscribed folders for username@gmail.com. Error: Cannot connect to the server. If you continue to receive this message, contact your server administrator or internet service provider (ISP).’

Outlook-Gmail sync error

CAUSE

This issue can occur if you add the Gmail account to Outlook and during browser sign in did not check the box for:

Select what Microsoft apps & services can access: “Read, compose, send, and permanently delete all your email from Gmail.”

MS apps & services wants access check box

STATUS: WORKAROUND

To work around this issue, it is necessary to remove the Gmail access for Microsoft apps & services and do the browser sign in from Outlook again. The steps below enable you to get back to the browser sign in where you can check that check box.

Step 1: Remove access for Microsoft Apps & Services in Gmail.

Close Outlook.
Sign in to your Google account on google.com.
Select your profile picture in the top corner and select Manage your Google Account.
On the left side menu, select Security.
Scroll down to Your connections to third-party apps & services and select Microsoft apps & services.
Locate Microsoft apps & services has some access to your Google Account and select See Details.
Under Access you’ve given to Microsoft apps & services, select Remove all access.
Select Confirm.

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

From the Windows Start menu, search for Credential Manager and open it. On Windows 10 you may need to open the Control Panel to access Credential Manager. For more information, please go to Accessing Credential Manager.
Under Manage your credentials, select Windows Credentials.
Scroll down to Generic credentials and locate those starting with MicrosoftOffice16_Data:OAUTH2.
Expand each of these and hover over MicrosoftOffice16_Data:OAUTH2 until it shows the full name including the tp_google_imap_Oauth2. These are the Google credentials for your Gmail account.
Select Remove for each of these with the MicrosoftOffice16_Data:OAUTH2. If you have multiple Gmail accounts, you will need to sign in to each of them again.
1. If you want to avoid removing Google IMAP credentials except for the specific affected account, you can map the credentials by comparing them to the identities in this registry key below. Open Registry Editor and paste this path in the Address bar at the top. Computer\HKEY_CURRENT_USER\Software\Microsoft\Office\16.0\Common\Identity\Identities
2. The sub keys to this registry key above include your Gmail identity. At the beginning of the identity registry key is a number that matches your Gmail credential in Credential Manager. See the examples below for reference.

After you have done the steps above you are now ready to Sign in via browser from Outlook. Open Outlook to the Outlook profile that was not syncing and select the Sign in via browser business bar in Outlook. Make sure during browser sign in to check the box for Microsoft apps & services noted at the top of this article.

sign in bar Outlook ribbon

If you removed the Gmail account from your Outlook profile, select File, Add account to add the Gmail account back again and do the browser sign in process again.