Does Microsoft Outlook hang constantly when you open the application on your Windows computer? Does the app occasionally freeze and show the “Microsoft Outlook Unresponsive” warning at random intervals?
In this guide you will learn why Microsoft Outlook is not responding in Windows and eight potential fixes for the problem.

Table of Contents
1. Force close and reopen Outlook
Terminating Outlook in Windows Task Manager can put things back in order.
- Right click on Start menu icon or press Windows key + Xand choose Workflow management in the Quick Access menu.

Quick tip: The Control + Change + Exit keyboard shortcuts are a faster way to launch Windows Task Manager.
- Go to the “Process” tab, select Microsoft Outlookand choose End of quest in the lower right corner.

If you can’t find Outlook in the “Process” tab, go to the “Details” tab, select OUTLOOK.EXEand choose End of quest.

- Option End of process on the confirmation prompt.

Open Microsoft Outlook again and check if the application works without crashes or crashes.
2. Run Outlook in Safe Mode
As mentioned earlier, Microsoft Outlook may become unresponsive if some pre-installed or third-party add-ins are affecting its performance. Start Outlook in Safe Mode will disable all plugins and other customizations when you launch the app. That will help you determine if a broken or conflicting add-in is the reason why Outlook is unresponsive.
- Click Windows key + CHEAP to open the Run box.
- Type or paste Outlook.exe / safe in the dialog box and select ALRIGHT or press enter.

If Windows fails to start Outlook in Safe Mode via the Run box, use the keyboard shortcut instead. Press and hold Ctrl key and select the Outlook app icon on the Desktop, Taskbar, or Start menu.
- You will receive a prompt asking you to confirm that you want to open Outlook in safe mode. Option Right proceed with.

- Select Outlook in the “Profile Name” drop-down menu and select ALRIGHT.

If Outlook works properly in safe mode, that tells you an add-in is responsible for the “Microsoft Outlook (Not Responding)” error. The next thing to do is disable all add-ins and restart Outlook.
- Option File on the menu bar.

- Option Option (or Than > Option) at the bottom of the left sidebar.

- Go Add page, select COM Add-ins in the “Manage” drop-down menu and select To go.

- Uncheck all plug-ins under “Available add-ons” and select ALRIGHT.

Close and reopen Outlook, re-enabling the disabled add-ins one by one to identify the broken/broken add-in causing Outlook problems.
- Go back to Outlook Add-ins page (see step #7) and check the add-in you want to enable and select ALRIGHT.

Close and reopen Outlook and repeat step #8 for all built-in or third-party add-ins in the list. If Outlook freezes and shows a “Microsoft Outlook Unresponsive” warning after enabling the add-in, that will let you know the source of the problem. Reopen Outlook in safe mode, disable the add-in, and relaunch Outlook.
3. Update Outlook
Outlook may sometimes become unresponsive on your PC if the version installed on your PC is outdated or has bugs. Connect your computer to the Internet and follow these steps:
- Open Outlook and select File on the menu bar.

- Option Office account on the sidebar.

- Choose Update options dropdown button.

- Option Update now.

That will launch the Microsoft Office Click to Run Client. The tool will update Outlook if a new version of the application is available. Otherwise, it will display the message “You are up to date!” warning if you have the latest version of Outlook installed on your PC.

Close the update client and try the next troubleshooting solution if the “Microsoft Outlook is not responding” problem persists.
4. Run Outlook Advanced Diagnostic Tool
Microsoft has an automatic diagnostic tool to fix problems with Outlook and other Office or Windows applications. Download the setup file, install the tool on your PC and follow the steps below. One more thing: make sure your PC is connected to the internet.
- Open the Start menu, type support microsoft in the search bar and open the selection Run as administrator in the “Microsoft Support and Recovery Support” menu.

- Option Opinion and choose Next.

- Choose the problem that best describes the problem with Outlook on your PC—Outlook won’t start, Outlook stops responding or freezesor Outlook keeps crashing with ‘Microsoft Outlook has stopped working’ message. Option Next proceed with.

- Choose Right and choose Next if you are running the diagnostic tool on the affected computer.

- Select your Microsoft account or select Use another account to sign in with another account.

Wait for the Outlook diagnostic tool on your computer and follow the recommendations. Try the other troubleshooting steps below if Microsoft Support and Recovery Support don’t fix the problem.
5. Reduce Outlook data files
Your Outlook inbox (and data) gets bigger as you send and receive more email. Outlook will take longer to open emails and perform other tasks if corrupted data file or too big. Outlook can even crash or sometimes become unresponsive during use.
Interestingly, Microsoft allows users to manually shrink or reduce the size of Outlook data files without having to delete messages and folders.
- Open Outlook, select File on the menu bar, select Account Settings drop down option and select Account Settings.

- Go Data Profile select the data file you want to reduce/compress and select Setting.

- Go Advanced tab and select Outlook data file settings.

- Option Compact now and choose ALRIGHT when Outlook finishes compressing the data file.

Close and reopen Outlook and monitor its performance. Repair the Outlook app if this does not fix the “Microsoft Outlook Unresponsive” problem.
6. Repair Outlook
Repairing Outlook can resolve issues that cause the app to misbehave when sending or reading email in your inbox. You can repair Outlook from the Windows Settings app or via the Control Panel.
Go Setting > Application > Apps and featuresselect the menu icon next to Microsoft Outlook, and choose Change.

To repair Outlook from Control Panel, open Control Panel> Programs > Program and featuresoption Microsoft Outlookand choose Change on the menu bar.

Select how you want to repair Outlook and select Repair.

Quick Repair is a self-repair process that scans for damaged files and replaces any damaged files with new copies available locally on your computer. It’s fast and doesn’t require an internet connection.
Otherwise, the online repair uninstalls Outlook from your PC and reinstalls a fresh copy from the Microsoft server. Operation requires internet connection. Plus, it also takes longer to complete.
We recommend running Quick Repair first. If the problem persists, reopen the repair tool and select Online Repair instead.

7. Restart your computer
Doing this will refresh Windows, close programs that conflict with Outlook, and fix other issues that cause Outlook to misbehave. Make sure you close all applications before restarting your PC, so that you don’t lose any unsaved work.
Press the Windows key or the Start menu icon, select the Power icon, and select Restart.

8. Update your computer
Windows updates are sometimes provided with updates for Microsoft Outlook and other Office applications. These updates fix an issue that prevents Outlook from opening or running correctly in Windows.
If you have a Windows 11 computer, open Setting application, select Windows Update on the sidebar and install or continue any available updates.

To install Windows Updates in Windows 10, go to Setting > Update & Security > Windows Update and choose Check for updates.
Stabilize Outlook in Windows
Some reports suggest that third-party anti-virus software can interfere with the performance of Outlook in Windows. If Outlook still crashes after trying these fixes, disable or uninstall your antivirus engine. Contact Microsoft Office support if the problem persists.