Outlook says it can't connect to server

Question

Outlook says it can't connect to server

Brian Schimpf 5

Outlook says it can't connect to the gmail server. This worked fine until yesterday. Windows did install a new update so that may have changed something. I've tried checking for instructions but they tell me to do things that don't exist.

Anonymous

2026-03-11T20:11:08.0466667+00:00

There is a current Known Issue with Gmail and Yahoo accounts. Please try the workaround in this article, https://support.microsoft.com/en-us/office/users-get-errors-0x800ccc0e-0x800ccc0f-synchronizing-gmail-and-yahoo-accounts-in-classic-outlook-e5a7b684-7c5c-4848-ab2d-d48291451f67.

As another alternative, the steps to clear the credentials in Credential manager under Manual Workaround Step 2 in this article may also work, https://support.microsoft.com/en-us/office/unable-to-add-a-gmail-account-to-classic-outlook-4d9530c5-3f40-4e6d-9b45-4477f160828f.
Scott Remington 0 Reputation points

2026-03-14T19:49:38.6666667+00:00

I purchased Office 2019 to fix the version and not allow MickeySoft to change things on their whim. With that version, the first support link above where you edit the registry worked for me (at least at this moment). I'm also using Win10 as my computer can't handle the bloatware of Win11.

1 answer

Your answer

Anonymous

2026-03-11T20:11:08.0466667+00:00

There is a current Known Issue with Gmail and Yahoo accounts. Please try the workaround in this article, https://support.microsoft.com/en-us/office/users-get-errors-0x800ccc0e-0x800ccc0f-synchronizing-gmail-and-yahoo-accounts-in-classic-outlook-e5a7b684-7c5c-4848-ab2d-d48291451f67.

As another alternative, the steps to clear the credentials in Credential manager under Manual Workaround Step 2 in this article may also work, https://support.microsoft.com/en-us/office/unable-to-add-a-gmail-account-to-classic-outlook-4d9530c5-3f40-4e6d-9b45-4477f160828f.
Scott Remington 0 Reputation points

2026-03-14T19:49:38.6666667+00:00

I purchased Office 2019 to fix the version and not allow MickeySoft to change things on their whim. With that version, the first support link above where you edit the registry worked for me (at least at this moment). I'm also using Win10 as my computer can't handle the bloatware of Win11.

Answer 1

The issue is likely related to recent changes in how Outlook connects to Gmail, combined with a recent Office/Windows update.

Use these steps that match classic Outlook with Gmail:

Confirm Outlook is on a fixed build

In Outlook classic, go to File > Office Account > About Outlook and check the version.
For the Gmail connection fixes, Outlook should be at least:
- Version 2404 (Build 17531.10000) or later for the sign-in fix.
- Version 2412 (Build 18324.20168) or later for the IMAP permission retry.
If the version is older, use File > Office Account > Update Options > Update Now to update Office.

Retry the Gmail permission prompt in Outlook If Outlook shows an error like:

“We couldn’t log on to the incoming (POP/IMAP) server…” or
“We weren’t able to set up your Google account with IMAP…”

And a Retry link is shown in the error window:

Select Retry.
A browser window opens to sign in to Google.
When prompted to allow Microsoft access, make sure the checkbox is selected for:
- “Read, compose, send, and permanently delete all your email from Gmail.”
Complete the sign-in and return to Outlook.

If this permission was not granted previously, Outlook will not be able to connect to the Gmail server until it is.

Check IMAP is enabled in Gmail If the error mentions IMAP or “may need to make changes to your Gmail settings,” verify IMAP:
In a browser, sign in at Gmail.com.
Select Settings (gear icon) > See all settings.
Go to Forwarding and POP/IMAP.
Under IMAP access, select Enable IMAP.
Select Save Changes.
Verify Gmail server settings (if using manual setup) If Outlook is configured manually, confirm the Gmail server details match:

Incoming (IMAP) server: imap.gmail.com, SSL required, Port 993
Outgoing (SMTP) server: smtp.gmail.com
- Requires SSL: Yes
- Requires TLS: Yes (if available)
- Requires authentication: Yes
- Port for SSL: 465
- Port for TLS/STARTTLS: 587
Username: full Gmail address
Password: Gmail password (or app password if using that method)

If sign-in is blocked as “not secure” If Outlook shows a message like “The browser or app may not be secure” when adding or syncing Gmail:

Ensure Outlook is updated to at least Version 2404 (Build 17531.10000), which changes sign-in to a separate browser window and resolves this.
After updating, remove the Gmail account from Outlook and add it again so the new sign-in flow is used.

If these steps are followed—update Outlook, re-grant Gmail permissions with the required checkbox, ensure IMAP is enabled, and confirm the server settings—Outlook should reconnect to the Gmail server.

References: