Outlook cannot synchronize subscribed folders Error: cannot connect to server

Question

Error Ox800CCC0E Outlook cannot synchronize subscribed folders Error: cannot connect to server

Answer 1

Hi, good day!

When was the last time it worked properly?

Are you trying to sync Gmail and Yahoo accounts with classic Outlook?

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If so, this is a recent issue and has been fixed by Microsoft. Please see the support article at the link below for more details.

https://support.microsoft.com/office/users-get-errors-0x800ccc0e-0x800ccc0f-synchronizing-gmail-and-yahoo-accounts-in-classic-outlook-e5a7b684-7c5c-4848-ab2d-d48291451f67

I look forward to your update and am happy to continue working with you until the issue is resolved. If you find the answer helpful, please click "Accept Answer" and consider upvoting it. Otherwise, please keep me posted by clicking "Add comments" below instead of selecting Yes or No.

Answer 2

Error 0x800CCC0E and the message “Outlook cannot synchronize subscribed folders / cannot connect to server” indicate a connection problem between Outlook and the mail server (often IMAP/POP).

Use these steps to troubleshoot:

1. Verify server and network connectivity

• Confirm the device has internet access.
• Check with the email provider (or their help pages) for the correct IMAP/POP and SMTP server names, ports, and encryption settings.
• In Outlook, go to File > Account Settings > Account Settings…, select the account, and verify the incoming/outgoing server settings match the provider’s requirements.

2. Repair the Outlook data file (PST/OST) Connection errors like 0x800CCC0E can be associated with a damaged data file.

• Run the Inbox Repair Tool as described in the article “Repair your Outlook personal folders file (.pst)”.
• After the repair completes, restart Outlook and test send/receive again.

3. Check for TLS 1.3 issues (IMAP/POP on Windows 10) If using IMAP/POP on Windows 10 and the server recently enabled newer TLS settings, Outlook may fail to connect.

• Follow the guidance to remove TLS 1.3 configuration:
  1. Open Regedit.
  2. Navigate to: Computer\HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\SecurityProviders\SCHANNEL\Protocols
  3. If a TLS 1.3 key exists under Protocols, export it as a backup, then delete the TLS 1.3 key and its subkeys.
  4. Restart Outlook; if sync still fails, restart Windows.

4. Recreate the mail profile If the error persists:

• Close Outlook.
• Open Control Panel > Mail > Show Profiles….
• Add a new profile and reconfigure the email account with the correct server settings.
• Start Outlook using the new profile and test synchronization.

5. If still failing

• Check with the email provider or ISP to confirm there is no server-side outage or blocking.
• If using security software or a firewall, temporarily disable it to see if it is blocking IMAP/POP connections (then re-enable and adjust settings as needed).

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References:

• I can't send or receive messages in Outlook
• Outlook IMAP or POP server unexpectedly terminated the connection, and the server was interrupted