How to Solve Outlook Won't Open Issue in Windows and Mac?

🕔 8 minutes read

Do you use Outlook on a daily basis? Chances are you come across problems, where the Outlook won’t open, freeze, or become unresponsive (stuck). This article explains how to fix Outlook not opening on Windows 11, 10, 8, or 7. However, if the issue seems to be caused by Outlook data file corruption, then make use of Remo Repair Outlook PST to easily repair severely corrupt PST files in Outlook with a few simple clicks.

Outlook application is a go-to application for all of our day-to-day work needs. It does it all, making appointments, sending emails, taking notes, and monitoring tasks. however, there may come a day when Microsoft Outlook will not open. The worst part is that Outlook not opening can prove to be a major obstacle as 80% of your work is dependent on it! (or at least in my case)

Knowing how important Outlook is, it is easy to spiral out and break into panic mode. However, I would say that there is still hope. as someone who has faced several Outlook not-opening issues myself, I have compiled all the tips and tricks I have learned along the way and presented my findings in the form of this article so that no one has to face the same issues that I did.

How to Fix Outlook Not Opening in Windows? 

Discussed here are several ways that are guaranteed to fix the problem of Outlook not opening on a computer.

  1. Disable Outlook Add-ins or toolbar extensions.
  2. Make sure that the outlook is not in compatibility mode.
  3. Try a different version of Outlook.
  4. Reset the Navigation pane.
  5. Scan the system for Viruses.
  6. Repair Corrupt Outlook Data.

Open Outlook in Safe Mode

First of all, we suggest you start Outlook in Safe Mode and try the methods mentioned below. Here is how you can open Outlook in safe mode.

Step 1:  Press Windows + R key.


Step 2: Type in Outlook /safe, and click on the OK button.


Step 3: Choose the Outlook Profile and click on OK.

Step 4: If asked for login credentials, enter your password and click on Accept.

Safe Mode is a feature that lets the user launch and run Microsoft Outlook with a restricted number of options and features also blocking extensions and add-ins. To help you troubleshoot minor issues or some bigger problems in Outlook.

Important Note: If you want to discover how to make boring activities in Outlook more enjoyable, take note. We suggest reading this post to learn how to use Quick Parts in Outlook to streamline routine activities.

Method 1: Disable Outlook Add-ins or toolbar extensions.

Using too many Outlook add-ins or extensions might also be the reason why the Outlook app won’t open on your Windows system. This can be due to unexpected or continuous conflict between two or more add-ins. We highly recommend our users try disabling the add-ins one by one and see which one was at fault.

Step 1: Launch the Outlook application.

Step 2: Find and click on File from the top of the screen.


Step 3: Click on options.


Step 4: A new window will appear on your screen, consisting of all the installed add-ins.

list of all add-ins appear

Step 5: Select Manage: COM Add-ins and click on the Go button.


Step 6: Uncheck the add-ins that you have decided to disable and click on OK.

select the add-ins you want to disable

Step 7: Close Outlook and try to restart the application. 

Method 2: Check if Outlook is in Compatibility Mode.

The Compatibility Mode is an inbuilt feature that is designed to run an older version of Microsoft Outlook on a newer version of Windows such as Windows 11 or 10. At times you might have accidentally enabled compatibility mode due to which Outlook is not opening in Windows 10 or other versions.
We suggest you check and disable the compatibility mode. 

Step 1: Open Outlook.

Step 2: Access the File menu and click on Options.


Step 3: Under General, select Optimize for Compatibility.


Step 4: Click on Apply and hit the OK button.

Method 3: Update to the Newer version of Outlook:

If the issue still persists, you can try a newer version of Outlook which is available. Upgrading to a newer version of Outlook might not just solve Outlook won’t load issues but also other problems such as the set of folders cannot be opened in Outlook.  

Follow the steps to install a newer version of the Outlook app on your computer system.

Step 1: Click on the File option from the top of the screen.


Step 2: Select the Office Account option from the drop-down menu.


Step 3: Click on Update Options.

Step 4: Click on the Update Now option to update the Outlook email client.


Method 4: Reset the Navigation Pane

There might be an issue with the navigation pane which is preventing Outlook to open and work properly. It makes sense to try resetting the navigation pane, whereby you get rid of all the customizations and optimizations made to the navigation pane in Outlook.

Step 1: Hit Windows Key + R key simultaneously.


Step 2: Type in the following command “Outlook.exe /resetnavpane” and click on OK.


Step 3: Launch Outlook. The navigation pane should be reset by now.

In some cases, this method works. If Outlook still does not open for you. Then kindly try the next method.

Method 5: Scan the system for Viruses.

A virus attack might be a possible reason why you are unable to open the Outlook application. That’s why we always suggest our users regularly run anti-virus scans on their systems to prevent any unexpected virus attack.  If in case you are not at all using any antivirus software. We highly suggest installing and using any reliable software. You can also use Windows Defender Firewall.

At times you might be able to open and run the Outlook application without any issues, but there might be certain issues like sent items not showing in the sent folder of Outlook or sudden disappearance of the draft emails from the drafts folder, or Outlook email not opening. All of these are signs of Outlook's profile getting corrupt.

Suppose all of the above methods have failed to fix the “Cannot Open Outlook in Windows” problem. Follow the next method that is guaranteed to repair corrupt Outlook data files.

Method 6: Repair Outlook Data Files

There are two ways to repair Outlook data files, one is by making use of ScanPST. This is a free DIY solution, which also has its own share of limitations and directly works on the original file, thereby putting your PST file at risk.

Hence we recommend a far better and safer way to repair your Outlook data file using a professional Outlook PST repair tool by Remo.

“If you're having trouble with Outlook, you must buy their software! I have hated Outlook for decades - it so permeates Windows and is so anti-intuitive. Thank God for Remo! They followed up time after time with me - not only repairing my corrupt Outlook pst file, but also aiding me in understanding some of the mysteries of Outlook. I simply could not be more pleased. Five stars!”- Clayton S Reynolds May 13, 2022

Source: Trustpilot

Remo Repair Outlook PST is an exclusive tool that is built for repairing corrupt Outlook data.  The tool can repair severely corrupted or damaged Outlook files with just 3 simple clicks on any version of Outlook. 

How to Repair Outlook Data File using Remo Repair Outlook PST

  1. Launch Outlook PST repair tool

    Download, Install, and Launch Remo Repair Outlook PST

  2. Import the Corrupted PST File

    from the main screen, and choose any one of the options depending on your needs.
    Open Default PST File: Finds the default location of your PST file.
    Select PST File Manually: Try this method if in case you know the location of the PST files that need to be repaired.
    Find All Your PST Files: This option deploys the algorithms to scan the entire drive and provide a list of all available PST Files. Use this option if you don’t know the location of corrupt PST files.
    Select the option to find the pst filechoose-outlook-file-import-method

  3. Choose between the two scan options.

    1. Normal Scan: Select this option if the level of corruption or damage is relatively low.
    2. Smart Scan: You can choose this option in either of the two situations. Firstly, when you want to repair and recover various data items such as emails, contacts, and notes from a severely corrupt or damaged PST file. Second, when the normal scan has failed.choose-scan-type

  4. Repair severely corrupt or damaged PST file

    Click on the Repair button to start the Outlook file repair. Once the scan is done, you can preview the repaired PST files.

  5. Verify Results

    If you are happy with the result. Kindly activate the tool and save the repaired Outlook files.

What to do when Outlook Won’t Open on Mac?

If you are wondering why you cannot start Microsoft Outlook on a Mac system or if the application becomes unresponsive or freezes unexpectedly. Then keep reading this section to find out an answer to fix the problem.

If you are using 14 versions of Microsoft Office or anything lower than that, the application will not run in Catalina or Big Sur. Office 2016 for Mac is no longer supported by Microsoft (no bug fixes or OS compatibility updates after October 2020). Office 2016 might or might not work on Big Sur.

So the easiest way to fix the problem is by updating Outlook.

How to Update to the Newest Version of Microsoft Outlook?

  • Step 1: Launch the Outlook App.
  • Step 2: Click on Help.
  • Step 3: Select Check for Updates.
  • Step 4: Choose Update and download the updates if available.


Here we end our discussion on how to repair Outlook not opening in Windows and Mac. if you have any additional questions, feel free to drop them in the comment section below.

Frequently Asked Questions

Why is Outlook not Working?

While there are several reasons, the most common ones are listed below-
1. Using faulty add-ins or extensions.
2. Corrupt Outlook Profile.
3. Virus or other Malware Attack.
4. Using an Outdated Version of Outlook.
5. Using an Outdated Version of Windows.

What happens if you clear the Outlook cache?

Clearing the Outlook cache will delete all the temporary files used by Outlook.  It can help with troubleshooting issues and remove any minor corruption or problems.
Clearing Outlook cache does not affect your Outlook emails, contacts, and other important data.

How do I fix Outlook that is not responding?

The most effective solutions to fix Outlook not responding are-
1. The most effective solutions to fix Outlook not responding are-
2. Disable Outlook Add-ins or toolbar extensions.
3. Make sure that the outlook is not in compatibility mode.
4. Try a different version of Outlook.
5. Reset the Navigation pane.
6. Scan the system for Viruses.
7. Repair Corrupt Outlook Data.

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Tony Landry

Tony Landry is a Web Content Editor at Remo Software. He loves to write, edit, and manage content for users trying to troubleshoot and fix problems on Windows, Outlook, storage drives, and Cloud storage networks. With an aptitude that transcends writing, Tony is recognized as a Microsoft Outlook, Word, and PowerPoint expert. His comprehensive solutions stem from an in-depth understanding of these tools, enhancing his standing as a trusted problem-solving resource.

He has published more than 200 articles on the Remo Software blog. He actively engages in research and problem-solving techniques to consistently generate great web content. Fixing various hardware problems on computer and storage devices along with a great knack for fixing Outlook errors, Tony is also the fun-time IT guy for all his work friends. Tony Landry’s work has been published in windowstechit, onlinegeeks, journeybytes and onlinecomputertips.

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