20 Fixes For Outlook Set Of Folders Cannot Be Opened Error on Windows

Microsoft Outlook is a simple tool and integrated with different Microsoft products like MS Office. Other than that, it comes with the Exchange connectivity feature that is very beneficial for enterprise-level email communication. Hence, this is a preferred email client for both firms and individuals alike.

Despite being one of the most popular email clients, Outlook can still give some errors while you use it. One such notorious error is “the set of folders cannot be opened.”

Getting this error means you won’t be able to access your Outlook emails and messages. There could be quite a few reasons behind this error. For example, corrupt pst or ost file or an improper Outlook setup.

Outlook set of folders cannot be opened error message

In this article, we will discuss some methods that can get rid of this error effectively. Although there is no direct way to solve it because we can’t be sure about the reason. Nonetheless, it is recommended that you try out the solutions one by one until the error gets resolved.

What Causes The Outlook Set Of Folders Cannot Be Opened Error?

Outlook is often preferred by users as an email client. However, just like other email services, Outlook also consists of some errors and that can interfere with your work. The exact cause behind the error is unknown but some of the suspected reasons are given below:

File Corruption

As per Microsoft, the main reason behind this error is a file corruption in the Outlook profile file, i.e. the .XML file that has your Outlook name on it.

Outlook Running In Compatibility Mode

The error can also arise if Outlook is trying to run in the Compatibility mode or if you are using a profile file such as .pst or .ost that was present in some old version of Outlook. Perhaps, this profile file is now deleted or has been damaged somehow.

Solutions To Get Rid Of Outlook Set Of Folders Cannot Be Opened Error

  1. Open The Outlook App In Safe Mode
  2. Disable Outlook Add-Ins
  3. Creating A New Account
  4. Open Outlook from the Taskbar
  5. Add A Password To Outlook App
  6. Remove The Account From The Mail App
  7. Get Rid Of .XML Files
  8. Reset Outlook’s Navigation Pane
  9. Log Out Of iCloud
  10. Reinstall iCloud
  11. Uninstall Exchange Server Cumulative Update
  12. Install The 64-Bit Version Of Ms Office
  13. Via Outlook Tools
  14. Place The .PST File In C Drive
  15. Not Using X To Close The Outlook Window
  16. Export Profile From Registry
  17. Fix The .OST File With Scanpst.exe
  18. Don’t Run Outlook In Compatibility Mode
  19. Update Outlook App
  20. Reinstall MS Office

Method 1. Open The Outlook App In Safe Mode

Launching the Microsoft Outlook app in safe mode will let you know the source of the problem, i.e. whether the issue is caused by the Outlook application itself or its add-ins. Given below are the steps you need to follow:

  1. Press the Windows + R keys to open up the Run utility.
  2. Enter “Outlook/safe” in the given field of Run utility and press the OK button
Outlook safe command in the Run tool
  1. A pop-up dialog box will show up asking you to choose your profile. Click the ‘OK’ button. If your account credentials are asked, enter your account password and select Accept

Check the status of Outlook from the top to know if it is running fine in Safe Mode. If Microsoft Outlook runs fine in the Safe Mode, in that case, there is an issue with the add-ins.

Method #2. Disable Outlook Add-Ins

If Microsoft Outlook is working alright in the Safe mode, try disabling the add-ins. To do so, follow the steps given below:

  1. Navigate to the File tab and click on Options > Add-ins
  2. Click “COM Add-ins” from the bottom located in the “Manage” box and select the “Go” button
Add-ins tab in the Outlook Options window
  1. A list of all the Add-ins will show up. Deselect all the entries in the list and click the “OK”
  2. Restart your Outlook service and check if this error goes away or not. If you are still facing the same error, move on to the next solutions.

Method #3. Creating A New Account

Your Outlook profile contains all your Outlook settings. Hence, if the profile is at fault, i.e. gets corrupted, then you could get the error “The set of folders cannot be opened” error. In this case, attempt creating a new Outlook profile:

  1. Open Control Panel and click on “Mail (MS Outlook 2016)”
  2. Click on “Show Profiles” and a new wizard will show up.
  3. Press the “Add” button. enter a name for your new profile.
  4. Go to the “Auto Account Setup” window and enter the details of your email account.
  5. Once your profile has been created, it will come up in the General tab in the Mail dialog box.
  6. Now from the section that says “When starting Outlook, use this profile,” choose the new profile from the drop-down menu that says “Always use this profile.” Click the OK button
  7. Restart the MS Outlook app and if it opens up without any errors, it confirms that the previous profile had been corrupted.

Method #4. Open Outlook from the Taskbar

Many users have claimed that the “Set of folders cannot open Outlook” error can be avoided if you start Outlook from the Taskbar. For this, you’ll need to have Outlook pinned to your Taskbar. 

  1. First, type in “outlook” in the Windows search bar, then select the “Pin to Taskbar” option.
Search result for the Outlook application
  1. Else, look for the Outlook shortcut from your desktop and drag it down to the Taskbar.
  2. Once done, right-click on the Outlook icon from the Taskbar and choose the “New Email Message” from the dropdown menu. This should open Outlook without any errors. Keep in mind that this is a workaround and won’t resolve the error permanently.

Method #5. Add A Password To Outlook App

A lot of users have claimed that the “the set of folders cannot be opened” error came up after they had finished linking their Gmail with Outlook. This happens if you have two-step verification enabled for your Gmail account.

The two-step verification is an amazing way to secure your email from unauthorized access. Hence, it is a great practice to set an app password for your Gmail app when you are linking your Gmail with the Outlook app.

Method #6. Remove The Account From The Mail App

You might already know that Windows comes with an in-built mail client known as Mail. If you have your mailing account in the Mail app and the same account is added on MS Outlook.

That can give rise to the “the set of folders cannot be opened” error. You can remove your account from the Windows Mail app by following the steps given below:

  1. Open the Mail app and navigate to the Accounts section from the left panel.
  2. From the Manage Account pane, click on the email account.
  3. Now, the Account Settings window will come up. Here, click on the Delete account option.
Email IDs in the Account settings window
  1. A pop-up will appear asking for your confirmation. Click the Delete button to proceed.
  2. Once you have removed your account from the Windows Mail application, restart the computer.

Method #7. Get Rid Of .XML Files

If your Outlook directory has XML files, this will be yet another reason behind the “the set of folders cannot be opened” error. In case the files get corrupted, that can lead to this error. Follow the steps given below to remove the .XML files from the Outlook directory:

  1. Press the Windows + R keys and enter Appdata in the field. Then, click the Enter button
  2. Now, the AppData directory will show up on the screen, go to the LocalMicrosoftOutlook16.
  3. Then, look for the XML files and change their location or delete them
  4. Restart the Outlook app and check if the error is gone or not.

Method #8. Reset Outlook’s Navigation Pane

The leftmost pane of MS Outlook is the navigation pane. It consists of all your Outlook folders and data files along with icons such as Contacts, People, Calendar, and Tasks. If you try resetting the navigation pane, it will get rid of the “the set of folders cannot be opened” error. Now, to reset the navigation panel in Outlook, follow the instructions given below:

  1. First, close all processes linked to Outlook
  2. Press the Windows + R keys together to open the Run utility
  3. Now, in the Run dialog box, type in “outlook.exe /resetnavpane” and press the Enter key
Reset navigation panel for Outlook command line
  1. Open the Outlook app again. If it runs fine now, then the error has been resolved.

Method #9. Log Out Of iCloud

Many users have reported that the error arises when you are using the iCloud and Outlook applications simultaneously. So, you can try logging out and then, logging back into iCloud to try and fix the issue. Follow the steps given below to do so:

  1. Close the Outlook app completely.
  2. Go to the Windows search bar and type in iCloud to open the Start Menu. Type in iCloud in the field and select the iCloud Desktop app when the search results come.
  3. when iCloud opens up, hit the Sign out button. Now, you’ll get a prompt asking you if you wish to keep other details like contacts, calendar, tasks, etc. Select the Delete from computer option.
  4. Once the contacts have been deleted, wait till the changes are applied.
  5. Log back into iCloud and select the option to sync Mail, Calendars, Contacts, and Tasks.

Method #10. Reinstall iCloud

Users have reported that iCloud might have some compatibility issues with the Outlook app. This can give rise to the “the set of folders cannot be opened” error. So, you can try reinstalling iCloud as an attempt to fix this issue. Follow the steps given below to do so:

  1. Open the Outlook app and navigate to File > Account Settings > Data Files.
  2. Next, look for the iCloud data file and click the Remove button. You will find it easily via its .aplzod extension. Now, a confirmation prompt will show up, click on Confirm.
  3. Close the Outlook window.
  4. Open the iCloud Control Panel and unmark Mail, Contacts, Calendars, and Tasks.
  5. Next, download and install the latest iCloud version. While installing, select the Repair option.
  6. Once iCloud is installed, restart the PC again.
  7. After your PC has restarted, start the iCloud Control Panel and choose Mail, Contacts, Calendars, and Tasks to start syncing them with Outlook.

Method #11. Uninstall Exchange Server Cumulative Update

It has been reported that sometimes, installing the Exchange Server Cumulative Update can also lead to the error. So, if you have this update installed, make sure to remove it. Then, check if the “the set of folders cannot be opened” error is gone or not.

Method #12. Install The 64-Bit Version Of Ms Office

If you are using a 32-bit version of Microsoft Office, that too can lead to the error. While using a 64-bit version of Windows, you need to uninstall the 32-bit version of Office and instead, install the 64 bit one. Users have claimed that this has successfully solved the “the set of folders cannot be opened” error.

Method #13. Via Outlook Tools

The Outlook tools app can also help you get rid of the “the set of folders cannot be opened” message. This third-party tool can help fix the issue. Follow the steps given below to use this:

  1. Download and then, install the latest Outlook Tools version.
  2. Launch the Outlook Tools app and go to Start-up Switches.
  3. From the left panel, choose Profiles > Start Outlook.
  4. Next, go to the Choose Profile panel. Choose the New option and enter a name for your profile.
  5. Click on Options and mark the checkbox next to Set as the default profile. Then, click on OK to save the changes.
  6. Type in all the necessary details required to set up your profile.
  7. Click Finish and now, the Outlook app should start on its own without giving any errors.

Method #14. Place The .PST File In C Drive

The “set of folders cannot be opened” error can also come up due to the .pst file being located on some other drive and not the C drive. In this case, moving the .pst file to your computer’s C drive might fix the error.

Method #15. Not Using X To Close The Outlook Window

Some users have claimed that the error shows up because they were using the X button to close the Outlook window. Hence, as a workaround, you can exit Outlook by going to File and then, clicking on Exit. This should help you start Outlook the next time without getting any errors.

Method #16. Export Profile From Registry

You can also get the “set of folders cannot be opened” error after you upgrade from MS Office 13 to MS Office 2016. In this situation, the users can’t set their profiles in the MS Outlook app. You can export your Outlook 2013 profile if you use a Registry Editor. To do so, follow the steps given below:

  1. Press the Windows + R keys and type in regedit in the field given. Press the Enter key or click on OK.
  2. From the left pane, go to the following key: HKEY_CURRENT_USER\SOFTWARE\MicrosoftOffice15.0\OutlookProfiles
  3. Now, right-click the Profiles key and select Export
  4. Select a location on your computer and set the file name as profile.reg. Hit the Save button
  5. Look for the profile.reg file in the location you have saved it in. Right-click on it and click on Edit.
  6. The Notepad will open up. Here, replace every 15.0 with 16.0 by pressing the CTRL + H keys. Enter 15.0 in the “Find what” field and 16.0 in the “Replace with” field. Then, click on “Replace All” and save the changes
  7. Next, run the profile.reg file
  8. A confirmation prompt will show up. Click on Yes to proceed. Now, your profile will get added to the Outlook app and you will be able to use it without any problems.

Method #17. Fix The .OST File With Scanpst.exe

Sometimes, a corruption with your .ost file can also lead to the “Outlook set of folders cannot be opened” error. This can be fixed with a repair tool for MS Outlook Inbox, scanpst.exe. Here are the steps you need to follow to do so:

  1. Open the Office Installation directory. It should be something like the following: C:\Program Files(x86)\MicrosoftOffice\Office16
  2. Look for scanpst.exe and run the file.
  3. Once the Microsoft Outlook Inbox Repair Tool starts, select the Browse option.
  4. Look for your .ost or .pst file. You should be able to find the .ost file in the following directory: C:\Users\your_username\MyDocuments\OutlookFiles. The .pst file should be located here: C:\Users\your_username\AppData\Local\MicrosoftOutlook. Either of these files can be used for the repair procedure.
  5. Choose the .pst or the .ost file and click on Start to scan the file.
  6. Once the scan gets finished, you’ll get a prompt asking you if you wish to repair the file. Click on Repair to initiate the repair process.

Note: You may need to execute the repair process a few times to completely fix all errors with Outlook.

After the repair is finished, Outlook should run fine without giving any errors.

Method #18. Don’t Run Outlook In Compatibility Mode

Some users claim that the “set of folders cannot be opened” error message comes due to running Outlook in Compatibility mode. You can change it by following the steps given below:

  1. Look for Outlook’s shortcut and right-click on it and choose Properties from the dropdown menu.
  2. Navigate to the Compatibility tab and unmark the Run this program in compatibility mode checkbox.
  3. Mark the Run this program as an administrator checkbox and hit the Apply button and then OK to save the changes.

Now, try starting Outlook again and check if the error gets resolved or not.

Method #19. Update Outlook App

  1. Navigate to File and click on Office Account.
  2. Visit the MS Office Update
  3. Select the Update Options
  4. Click on the Update now option

Method #20. Reinstall MS Office

Microsoft Outlook app is a part of the MS Office package. So, reinstalling Office on your system might get rid of the “set of folders cannot be opened” error. Reinstallation can reset Microsoft Outlook entirely and that could get rid of the cause of the error.

Moreover, it is recommended that you install a 64-bit version of Microsoft Office instead of the 32-bit version. The reason is that very few cases of the “set of folders cannot be opened” error have been seen with the 64-bit version.

Conclusion

The above solutions should help you get rid of the “Outlook set of folders cannot be opened” error. You can try several fixes from repairing the PSTs to reinstalling Office and so on. Hopefully, the above methods were easy to understand and have helped resolve the “the set of folders cannot be opened” error.

FAQs

How Do I Fix Outlook 365 Search?

You can try rebuilding the index of Outlook 365. Select Options and then, choose Search. Next, select Indexing Options and now, you’ll find which locations you need to index. Hit the Advanced button and then, select the rebuild option in the Troubleshooting section.

What Causes Invalid XML In Outlook?

If the XML files of Outlook got corrupted or damaged somehow, that can give rise to the invalid XML error. Sometimes, if you are using a previous version’s Outlook profile, that too can be the reason behind this error.

How Do You Fix The Cannot Start Outlook Set Of Folders Cannot Be Opened?

There are a couple of solutions you can try to fix this error. Some such methods include creating a new Outlook profile, clearing out the credential manager, switching to the x64 bit version of MS Office, and so on.