How To Fix Outlook Cannot Expand The Folder Error?

Outlook Cannot Expand The Folder Error

No other email client is as important as Microsoft Outlook, especially for managing personal and business email. Although it is the largest and most reliable email application, it is not safe from technical errors. One of the common errors that usually appear in Outlook cannot expand folder error. Such an error message appears when you try to open a specific folder in your MS Outlook account. Whatever folder you want to expand, whether it’s a shared folder, public folder, address book, or secondary mailbox, you can deal with this problem.

Read: How to Fix Outlook Not Working on iPhone Error?

Although this error is awful, the blog is more than willing to help you with an extensive solution guide. So, keep an eye on the repair tips to fix the problem quickly.

Behind the Reason for Outlook Cannot Expand The Folder Error?

Malicious factors can cause Unable to display folders error in Outlook. Given below is the list of reasons that are responsible for this problem. let’s take a look:

  • Cached Exchange Mode is probably enabled.
  • Due to interference of third-party add-ons.
  • A corrupted or damaged Outlook profile can also trigger Outlook cannot expand folder errors.
  • Malfunction in MS Outlook OST/PST file.
  • Problems with Microsoft Office applications.
  • Folder visible permission cannot be set.
  • When there is not enough memory to view shared folders in Outlook.
  • Faulty configuration in Outlook can also cause the same problem.

Effective Solutions to fix Outlook Cannot Expand Folder Error

Below we have listed various effective solutions that will have an effect on solving your error. Thus, don’t worry if a set of folders cannot be opened in Outlook. All you need to do is apply the following troubleshooting tips and fix your problem. Let’s start following!

Solution 1: Enable the Visible Folders option

Enabling the “Folder Visible” option in MS Outlook resolves the “Could not expand folder” error immediately. Here’s the step-by-step process to make a folder visible:

  • Firstly, launch MS Outlook on your Windows PC.
  • Next, right-click on the mailbox that appears in the folder list.
  • Select the “Properties” option from the menu bar.
  • Then, in the “Permissions” tab, select the “Visible folders” option.
  • Finally, click “OK” to save the changes.

Now feel free to open the shared folder in your mailbox. If the folder still doesn’t expand, move on to the next troubleshooting tips.

Solution 2: Disable Cached Mode

Disabling Cached Exchange Mode eventually updates the mailbox with the server that is running Microsoft Exchange. Moreover, it will be helpful to access all the data effortlessly and even without any hindrance. So, whenever you can’t open/expand a shared folder in Outlook, turn off Cached Mode. This way:

  • First open Outlook.
  • Then navigate to File > Account Settings > Account Settings.
  • Now, on the “Account Settings” page, under the “Email” section, double-click the account that can’t see the folder in Outlook.
  • Now it will open the “Change Account” page.
  • Here, just below the “Offline Settings” section, you’ll see a “Use Cached Exchange Mode” checkbox. If it is already selected, uncheck the box by clicking on the checkbox to deselect it.
  • Now press the “Next” button to continue following further instructions and save the settings you have changed.
  • Now reopen Microsoft Outlook and try expanding the folder again.

If Microsoft Outlook cannot expand the folder’s shared mailbox at this time, go to the next repair method.

Solution 3: Disable Third-Party Add-ins

Pre-installed third-party add-ins may interfere when you are synchronizing the mailbox and therefore hurt the functionality of the application. They would become a snag for the smooth functioning of the Outlook application. Therefore, if Outlook 2016 cannot expand the folder, the most effective technique is to disable Microsoft Outlook add-ins. The complete steps to do so are listed below:

  • Firstly, launch the MS Outlook application.
  • Then go to the “File” menu, select “Info” and click on the “Options” tab.
  • You will then be redirected to the “Outlook Options” page.
  • Here, click on the “Add-ons” tab.
  • Next, go to the lower right panel and click the “Go” button against Manage > COM Add-ins.
  • Now deselect the add-ins and then click on the “OK” tab.
  • After that, open your Microsoft Outlook account again and try expanding the folder again to check if it works.

Solution 4: Repair MS Outlook

Outlook applications can get corrupted due to technical issues or some bugs. So, assuming this to be the real reason, you can try to perform an online repair on your Microsoft Office suite. But, before running it, make sure that you have a strong network connection on your Windows PC. Now, follow the steps given below:

  • First, open the “Control Panel” from the Start button.
  • Then, under “Programs and Features”, click on the “Uninstall a program” tab.
  • Next, find the standalone Outlook application or select the installed Microsoft Office program.
  • Then click on the “Edit” button at the top.
  • If prompted, click “Yes” to continue.
  • A pop-up window will appear with two options.
  • When you click on the “Quick Repair” toggle button, it will work offline and fix most of the common errors quickly and efficiently. If that doesn’t work, you can try “Online Repair” by clicking its toggle button.
  • Outlook application repair processing time depends on the network speed. So, if you have a stable internet connection, the repair process will be completed sooner.
  •        Once the repair is done, try accessing the folder with your Outlook account.

Hopefully, this time Outlook can expand the shared folder. But, if this is still not the case, apply the following repair tips.

Solution 5: Create a New Outlook Profile

A damaged or corrupted Outlook profile can be the main reason Outlook cannot expand folder delegate mailbox problems. Hence, simply creating a new Outlook profile would be a one-stop solution to this problem. Let’s do it now!

  • Firstly, launch the MS Outlook application.
  • Next, go to the “File” menu and click on the “Account Settings” drop-down button to select “Manage Profile”.
  • Next, in the “Mail Setup” dialog box, click on the “Show Profile” option.
  • Then click on the “Add” button to create a new profile.
  • Now give a name to the Outlook profile and enter your email account details.
  • After that, tap on “OK”.
  • Now set the newly created profile to your default account by selecting the option “Always use this profile”.
  • Finally, click “OK”.
  • Now open the Outlook application with this new profile and check whether you can expand a folder or not.

Opening a new profile in Outlook will give you a fresh start and the profile with the corruption will be permanently removed forever.

Solution 6: Repair Outlook PST/OST file

If you’re using an IMAP or POP account, all Outlook email data is saved in a .PST file. But, if you’re using an Office 365 or Exchange account, that same email data is stored in an .OST file. Therefore, Outlook cannot expand the folder if a data file is corrupted. This is the reason why it is widely necessary to check for and repair damaged files. This way:

Repair OST File

  • First, open the Control Panel on your Windows
  • Now click on the “User Accounts” tab and select the “Mail” option.
  • Next, click on the “Data Files” tab.
  • Then select the account that is causing problems when expanding a folder in Outlook and click “Open file location…”.
  • Now delete the .OST file at that location, restart your computer and try reaccessing your Outlook account to expand the shared folder.

Repair PST File

  • Press Windows + R keys together to bring up the Run dialog box.
  • If you are using MS Office 2016, 2019 or 365, type the path “C:\Program Files (x86)\Microsoft Office\root\Office16” in the search field and press “Enter”.
  • If you’re using Outlook 2013, enter the file path “C:\Program Files (x86)\Microsoft Office\Office15” in the Search field, then press OK.
  • Double-click the “SCANPST.exe” file in the directory.
  • Next, click on the “Browse” button and navigate to your PST file.
  • Data files are automatically saved in the Documents folder.
  • Click on the “Start” button and wait for the .pst file to be completely recovered.

After repairing your Outlook data file, you probably want to expand a folder in your Outlook profile.

Solution 7: Expand the folder limit

The maximum limit set for MS Outlook is 1000 folders. So, if in any case, the limit exceeds the specified number, an additional folder will become inaccessible and cannot be expanded either. Although the folder limit is 500 for Outlook 2010, 2013, 2016, and 2019 versions, each folder can contain up to 100,000 files.

So if one of you has exceeded your limit, accessing a specific folder can be awful. In this case, take a backup of your important emails and delete all unwanted emails or folders. Deleting irrelevant emails will save more storage space on your hard drive and therefore allow access to any folder


Hope you are satisfied enough with the above troubleshooting guide to fix Outlook cannot expand folder error. The solutions described above are easy to understand and easy to implement. If, you face any issues while performing the solution methods, feel free to consult Outlook online support team 24×7. Useful treatments will be provided to you in a short time.