Ways to Troubleshoot Outlook Error 0x800CCC67
Written By Aaruni Arora 
Updated On September 24, 2026 Written By Aaruni Arora Updated On September 24, 2026 Outlook error 0x800CCC67 is a common send/receive error that occurs because of incorrect account settings. The good thing is that it can be easily fixed once the underlying cause is identified. In this blog, we will discuss the factors that cause this error, as well as the solutions to resolve this Outlook '0x800CCC67' error easily.
Outlook displays a temporary error 0x800CCC67 when it fails to send emails because of a connection issue. This is usually an SMTP 421 response where the server is unable to go forward with the connection request. You might notice the following symptoms when Outlook faces this error:
If you are facing any of these messages or scenarios, then you might be facing the Outlook error 0x800CCC67. So, let's understand the reasons behind this error.
This error can occur because of disabled SMTP authentication or incorrect port settings. We’ve listed some other common reasons for this error below:
There are different methods available to fix the 0x800CCC67 error. Here, we have covered the most reliable solutions to fix the error.
Before attempting any other method, check your internet connection to see if it’s working well or not. Open your browser and try to load some other sites to verify if it’s an internet issue. If you’re using VPN, turn it off temporarily and try sending the email again.
Incorrect SMTP port settings are one of the most common causes of this error. So, you need to check whether the SMTP port is correct or not. To check this, follow the steps below:
If the problem still exists, then turn the router off for an entire minute and turn the power on again to verify it.
Outlook can show the 0x800ccc67 error if Outlook takes too long to connect to the outgoing email server. If you've a poor internet connection or your email attachment size is too large, the server might time out, and you'll see this error. Increasing the timeout limit can prevent it from happening. Follow the steps below to increase your server timeout limit in Outlook:
Note: This method only works for Classic Outlook. New Outlook doesn't offer a feature to manually adjust server timeout settings.
Antivirus installed on your system could also be a reason behind this error. It usually scans the emails for any suspicious files, and if it finds one, the antivirus flags it as dangerous. Temporarily disable the email outgoing scan feature of your antivirus and check if the email is getting delivered or not. Turn your antivirus on again once you've verified if this is what's causing the error.
If you still can't send an email after trying all the methods, try creating a fresh user profile to see if this helps. Creating a new profile will help you set up your Outlook account settings from scratch. This will help you understand if the Outlook profile is causing the problem or not.
Common scenarios like unstable network connection or incorrect SMTP settings can be the reason for the Outlook error 0x800ccc67. Starting with the simplest fixes, we've given some effective ways to fix this error according to what's causing this error. After troubleshooting, if you find out that your PST file is damaged, you can use ScanPST.exe to check for any errors and repair the data file. If the PST file can't be accessed even after using ScanPST.exe, a dedicated PST Repair tool can help in this case.
A: If you keep facing the error 0x800ccc67 in Outlook repeatedly, maybe the underlying cause for it isn't resolved. Check the SMTP settings of your account or the server timeout limit.
A: Not necessarily. If the issue is with the SMTP settings, your emails won't be affected. However, if the issue is with your Outlook profile or data file, then your emails might get affected.