How to fix Outlook errors 0x800CCC0E and 0x800CCC0F
These mean Outlook could not reach the mail server, either timing out or being refused. They often hit third-party accounts with the wrong ports or SSL settings. Jump to your situation below or work through the methods in order.
By Neeraj Singh ~7 min Updated Jun 2026 87% found this helpful
Error message
0x800CCC0E / 0x800CCC0F. The connection to the server timed out or was refused.
Summary
Outlook errors 0x800CCC0E and 0x800CCC0F mean the app could not establish a connection to the mail server: the connection either timed out or was actively refused. They frequently appear on third-party accounts such as Gmail or Yahoo added to New Outlook, where the server addresses, ports or SSL/TLS settings do not match what the provider requires, or where a firewall or antivirus is blocking the connection. The fix is to verify the incoming and outgoing server names and ports (commonly IMAP 993, POP 995, SMTP 465 or 587) with SSL/TLS enabled, confirm the account password or app password is current, check that a firewall or security tool is not blocking Outlook, and re-add the account if its settings drifted. Correct server settings clear the error in most cases.
What this error means
To send and receive, Outlook opens a network connection to your provider's incoming and outgoing servers on specific ports. 0x800CCC0E means that connection did not complete in time, and 0x800CCC0F means the server refused it. Either way, no session was established.
The usual reason is a settings mismatch on a manually added account: a wrong server name, the wrong port, or SSL/TLS not set the way the provider expects. A firewall or antivirus blocking Outlook produces the same symptom. Matching the provider's documented settings restores the connection.
Common causes
Wrong incoming or outgoing server address.
Incorrect port numbers for IMAP, POP or SMTP.
SSL or TLS not enabled or set incorrectly.
A firewall or antivirus blocking Outlook.
An outdated password or a missing app password.
A temporary network or server outage.
Expert insight
“0x800CCC0E and 0x800CCC0F are connection errors, timed out or refused. On New Outlook they usually show up on a Gmail or Yahoo account where the ports or SSL are not quite right. So I check the server names and ports against the provider's docs, IMAP 993, SMTP 465 or 587 with SSL on, and confirm the password or app password is current. If the settings are right, I look at whether a firewall or antivirus is sitting in the way. Get the settings matched and the connection comes back.”
Manager, Tech Support & Operations · 19+ years fixing Windows and system errors
✓ How to fix it
Method 1
Verify server addresses and ports
1Check the incoming and outgoing server names and ports against your provider's documentation.
2Common values: IMAP 993, POP 995, SMTP 465 or 587, with SSL/TLS enabled.
3Correct any mismatch and test send and receive.
Method 2
Confirm the password or app password
1Make sure the account password is current.
2For Gmail, Yahoo and similar, you may need an app password rather than the normal one.
3Update it in the account settings.
Method 3
Check the firewall and antivirus
1Confirm a firewall or antivirus is not blocking Outlook's connection.
2Add Outlook as an exception, or test with the security tool briefly paused.
3Re-enable protection afterwards.
Method 4
Remove and re-add the account
1If settings drifted, remove the account from Outlook and add it again.
2Let Outlook auto-configure, or enter the verified server settings manually.
3This rebuilds a clean connection profile.
Method 5
Rule out a provider outage
1Check your provider's service status to rule out a temporary server outage.
2If the server is down, wait and retry.
0x800CCC0E and 0x800CCC0F are connection errors, so verify the server addresses and ports (IMAP 993, SMTP 465 or 587 with SSL/TLS) and confirm the password or app password is current. If the settings are right, check that a firewall or antivirus is not blocking Outlook, and re-add the account if its settings drifted.
Frequently asked questions
What do Outlook errors 0x800CCC0E and 0x800CCC0F mean?
They mean Outlook could not connect to the mail server. 0x800CCC0E is a connection timeout and 0x800CCC0F is a refused connection. Neither established a session with the server.
How do I fix them?
Verify the incoming and outgoing server names and ports against your provider (IMAP 993, SMTP 465 or 587 with SSL/TLS), confirm the password or app password, and check that no firewall or antivirus is blocking Outlook.
Why do they hit Gmail or Yahoo accounts?
Third-party accounts added manually often have a port or SSL mismatch, or need an app password. Matching the provider's documented settings and using an app password resolves it.
Which ports should I use?
Typically IMAP 993 and SMTP 465 or 587 with SSL/TLS for modern setups, or POP 995. Confirm the exact values in your provider's help pages, since they vary.
Could antivirus cause this?
Yes. A firewall or antivirus can block Outlook's connection, producing a timeout or refusal. Add Outlook as an exception, or test with the tool briefly paused, then re-enable it.
It still fails with correct settings
Remove and re-add the account to rebuild a clean profile, and check your provider's service status to rule out a temporary outage.
Still not working?
If the settings are verified and no security tool is blocking Outlook but the connection still fails, your provider may require an app password or OAuth2 sign-in that the manual setup is not using; re-adding the account with modern authentication usually resolves it. You can also submit your error to us for a tailored fix.
