Outlook not sending and receiving gmail emails since Feb 26, 2026

Followed this procedure, but the historical emails have not synched into New Outlook. I did get them to sync in old Outlook.....Ideas?

So we made progress.

How are these Settings set?

This article should help you out:

Gmail Not Working in Outlook 365? Here's the Proven Fix (2026)

See the steps below to fix Gmail in Outlook classic during Setup:

Press Windows + S, type Credential Manager, and open it.

Click Windows Credentials.

Scroll to Generic Credentials.

Find entries starting with MicrosoftOffice16_Data:OAUTH2.

Expand each entry.

Hover over MicrosoftOffice16_Data:OAUTH2 to see the full name containing tp_google_imap_Oauth2 (these are Gmail credentials).

Click Remove for each MicrosoftOffice16_Data:OAUTH2 entry.

Remove both credentials for the affected Gmail account.

Optional: To identify the correct Gmail account before deleting:

Open Registry Editor.

Paste this path in the address bar:

Computer\HKEY_CURRENT_USER\Software\Microsoft\Office\16.0\Common\Identity\Identities

Check the Identity subkeys.

The number at the beginning of the identity key matches the number in the MicrosoftOffice16_Data credential.

After removing the credentials:

Open Outlook.

Go to the affected profile.

Click Sign in via browser in the Outlook notification bar.

Sign in to your Gmail account again.

Remove access for Microsoft Apps & Services in Gmail (Fix Gmail in Outlook Sync)

Close Outlook.

Go to google.com and sign in to your Google account.

Click your profile picture in the top-right corner.

Select Manage your Google Account.

From the left menu, click Security.

Scroll to Your connections to third-party apps & services.

Select Microsoft apps & services.

Find Microsoft apps & services has some access to your Google Account.

Click See details.

Under Access you’ve given to Microsoft apps & services, click Remove all access. This should reset the Gmail in Outlook sync, and you can try again.

Select Confirm.

The issue is most likely related to recent changes in how Gmail accounts authenticate with classic Outlook, not specifically to a Windows update. There are two main areas to check and correct: Gmail’s IMAP settings and the Outlook–Google consent/connection.

Follow these steps in order:

1. Confirm Outlook is online and connected

• In classic Outlook, look at the status bar at the bottom.
• If it shows Disconnected, Working Offline, or Trying to connect…, go to Send/Receive tab > Work Offline to toggle back online.
• After it shows as connected, try Send/Receive again.

2. Verify IMAP is enabled in Gmail Gmail must have IMAP enabled or Outlook will fail with IMAP errors.
3. In a browser, sign in to Gmail.
4. Select the gear icon > Settings.
5. Go to Forwarding and POP/IMAP.
6. Under IMAP access, make sure Enable IMAP is selected.
7. Select Save Changes.

If IMAP was disabled, re‑start Outlook and test send/receive.

3. Reconnect Gmail to Outlook with correct permissions If the Gmail account was added previously and the consent box for full mail access was not checked, Outlook can no longer sync and will show IMAP/connection errors.

For classic Outlook builds with the fix (Current Channel Version 2412 Build 18324.20168 or later):

1. When the error dialog appears for the Gmail account, select the Retry link.
2. A browser window opens for Google sign‑in.
3. Sign in to the same Gmail account.
4. On the consent screen, under Select what Microsoft apps & services can access, ensure the option “Read, compose, send, and permanently delete all your email from Gmail.” is checked.
5. Complete the sign‑in and return to Outlook; then try Send/Receive.

If the Retry flow does not appear or does not work, remove and re‑add the Gmail account after confirming IMAP is enabled, and during the add process make sure that same permission box is checked.

4. Confirm server settings if using manual configuration If the account is configured manually as IMAP/SMTP, verify the Gmail server settings match:

• Incoming (IMAP):
  • Server: imap.gmail.com
  • Port: 993
  • SSL: Required (Yes)
• Outgoing (SMTP):
  • Server: smtp.gmail.com
  • SSL: Yes, Port 465 or
  • TLS/STARTTLS: Yes, Port 587
  • Authentication: Required (same username/password as incoming)

5. Check for other common Outlook send/receive blockers If the Gmail connection and IMAP settings are correct but mail still does not move:

• Ensure there is no oversized message stuck in Outbox (especially with attachments > ~20 MB). If present, open it, remove or reduce the attachment, or delete the message, then send again.
• Make sure the internet connection is working by opening a browser and visiting a site such as http://www.microsoft.com.
• If problems persist only in this Outlook profile, repair the profile or create a new one using the steps in Fix your Outlook email connection by repairing your profile / Create an Outlook profile.
• If Outlook itself appears unstable after recent updates, run an Office repair using Repair an Office application.

6. About whether and when it will be fixed For the known Gmail sign‑in/add‑account issues in classic Outlook, Microsoft has already released fixes in current channels by changing the sign‑in flow to a separate browser window. If Outlook is updated to one of the fixed builds and the Gmail account is re‑consented with full mail access and IMAP enabled, the Gmail send/receive issue should be resolved without waiting for another Windows update.

If, after all of the above, Gmail still does not send/receive in classic Outlook while it works in the browser, capture the exact error text from the Send/Receive dialog and contact Outlook support or post it in the Outlook Tech Community for further investigation.

References:

• Unable to add a Gmail account to classic Outlook
• Unable to sign in or add a Gmail account to classic Outlook
• Fix problems connecting your Google account to the Microsoft Cloud
• I can't send or receive messages in Outlook