How to fix Outlook error: The set of folders cannot be opened

Your Outlook account has several mail profiles, but now you cannot start Microsoft Outlook or open the Outlook window. The error shows: Cannot start Microsoft Outlook. Cannot open the Outlook window. The set of folders cannot be opened. The operation failed. In this article, you will learn how to fix Outlook error: The set of folders cannot be opened.

Cannot start Microsoft Outlook error

You open the Microsoft Outlook app, and the below error appears:

The Microsoft Outlook app doesn’t open on your computer, and you are stuck. You tried multiple ways, like:

• Updating, repairing, and reinstalling the Outlook application
• Removing the Outlook profile from the Control Panel
• Starting Outlook in safe mode
• Disable Outlook add-ins

Unfortunately, nothing of the above works and Outlook still shows an error. Read the next steps to fix the error and start Microsoft Outlook.

Solution to Outlook error: The set of folders cannot be opened

To fix the Outlook error is to recreate the Outlook email profile. Therefore, you need to delete all the profiles you have in your Outlook app. See the following steps to delete all the profile folders.

Step 1. Open Registry Editor

Go through the below steps to open the Registry Editor:

1. Go to the Windows search bar
2. Type Registry Editor
3. Click Run as administrator to open the app

4. The Registry Editor app opens

Step 2. Navigate to Outlook Profiles

Navigate to Computer\HKEY_CURRENT_USER\SOFTWARE\Microsoft\Office\16.0\Outlook\Profiles, as you can see in the screenshot below.

The value represents your Microsoft Office version:

• 16.0 (Office 2016, Office 2019, Office 2021, Microsoft 365)
• 15.0 (Office 2013)
• 14.0 (Office 2010)

Step 3. Delete folders

You need to delete all the folders listed under Profiles.

1. Right-click the folders and click Delete
2. Click Yes

3. It shows that there are no folders under Profiles

Step 4. Restart computer

Close the Registry Editor app and restart the computer. It’s essential to reboot the computer to have the changes take effect.

Check Outlook error fix

To verify the Outlook error is fixed, open the Outlook app.

The error message Cannot start Microsoft Outlook. Cannot open the Outlook window. The set of folders cannot be opened. The operation failed. doesn’t appear anymore, and it’s fixed.

The last step is to add the profile account in Outlook.

Create new profile in Outlook

You can open the Outlook app and create a new profile. In our example, we will add the user Amanda.Hansen@m365info.com

Follow the steps to create a new profile in Outlook:

1. Type Outlook
2. Click OK

3. Type the email address (Amanda.Hansen@m365info.com)
4. Click Connect

5. It shows Account successfully added
6. Click Done

You can successfully open the Outlook app with the account you added!

Read more: How to import Google contacts to Outlook »

Conclusion

You learned how to fix the Outlook error The set of folders cannot be opened. If you can’t access the Outlook app, open the Registry Editor and delete the folders under Outlook Profiles. This will delete all the user profiles in your Outlook. Next, you need to restart Outlook and create a new profile to add the account.

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