Almost every organization has started relying on MS Outlook for sending/receiving emails. Though using Outlook is simple and easy, there are many errors encountered by users that make it a little challenging to use MS Outlook. One such error is '0x800CCC67,' which is widely faced by Outlook users.

We will discuss the factors that cause this error, as well as we will talk about the solutions that can be used to resolve MS Outlook '0x800CCC67' error.

Reasons behind Outlook 0x800CCC67 error

There are no fixed reasons for the Outlook 0x800CCC67 error, as many scenarios can cause this error. Some causes of this error are:

  • Incomplete download or installing Outlook for the first time on a new system
  • Removal of Outlook related files by some third-party applications
  • Due to malware or virus infection
  • If the registry files get corrupted due to MS Outlook installation
Messages you get with 0x800CCC67 error

When MS Outlook if suffering from 0x800CCC67, you will receive the following error messages on your screen.

  • Error 0x800CCC67 appears on the screen, and MS Outlook crashes immediately
  • "SMTP_421_NOT_AVAILABLE" message appears on the screen
  • The computer starts freezing repeatedly
  • Windows becomes slow and provides a late response to any input

If you are facing any of these messages or scenarios, then the MS Outlook is facing the 0x800CCC67 error. So, let's move to the solutions to fix this error.

Methods to Fix Outlook 0x800CCC67 Error

There are different methods available to fix the 0x800CCC67 error. Here we have covered the most reliable solutions to fix the errors.

Registry File Repair

The first method to resolve the error is repairing or editing the registry files of Windows. But, make sure you have enough understanding of editing registry files, else it could cause issues.

Disable the antivirus

Antivirus installed on your system could also be a reason behind this error. But we are not talking about the pre-installed antivirus on your system. We are talking about the third-party antivirus that you have installed on your system. For example, if you have installed AVG antivirus on your system, disable it.

Reinstall MS Outlook on your System

Another method that can be utilized to fix the error is reinstalling MS Outlook on the system. Now, whether you're using Outlook 2007 or 2016, the installation process depends on the operating system. Here, we will tell you how to reinstall Outlook on Windows 10.

  1. Go to the Start menu and search for MS Outlook.
  2. Right-click on the MS Outlook icon to check the available options.
  3. Click Uninstall to remove Outlook from your windows.

After uninstalling MS Outlook, you can easily reinstall it from the downloaded file.

Change the SMTP port

There are several ports used while using an email application, and SMTP is the most important ports amongst them. So, you need to check whether the SMTP port is right or not. To check this, go to the email settings and check for the mentioned port under the outgoing mail server.

After modifying the ports, try to send the email again. However, if the problem still exists, then turn the router off for an entire minute and turn the power on again to verify it.

Scan the system for virus or malware

Sometimes, a virus or malware can cause Outlook to behave improperly or cause this error. That's why it is strongly recommended to scan your system for any virus or malware activities. You can use the in-built Firewall by Microsoft to remove any virus from the system. And if you don't have an anti-virus, install it immediately and check for any virus.

Restore the system

Restoring your system allows you to restore all your settings so that the installed applications work properly. In order to restore your system in Windows 10, you should have enabled it first. With this feature, you restore the settings of the system to a previous restore point so that all the applications and settings of that point are restored.

Use a professional Outlook Repair tool

If none of the above methods work in fixing the 0x800CCC67 error, then chances are the PST file is corrupted and is causing the error. In such cases, it is recommended to repair the PST file. To repair PST files, there are only limited options available. So, we recommend you use the Kernel Outlook PST Repair tool, which is designed to fix the corruption and errors of Outlook PST files. With this tool, you can repair a PST file of any size.


It is very common to encounter errors in Outlook, as this application is hundred percent perfect. But, some errors often cause much problem than other errors, and error 0x800CCC67 is amongst those errors. So, we discussed the common reasons behind this error, as well as provided practical solutions to resolve this error.