What to Do When Microsoft Outlook Won't Open

If you're trying to open Microsoft Outlook from your Start menu or a shortcut icon but it just won't launch, don't worry, there are a few things you can try to get it up and running again. Here are some common fixes that should work when Outlook doesn't open, whether you're using Windows or a Mac.

Reasons Why You Can't Start Outlook

Several issues could cause Outlook to open incorrectly or not at all. Some common culprits include:

• Problematic add-ins
• Damaged files
• A corrupted profile
• Navigation pane issues

There are other issues, too, that can contribute. Maybe you've added a new program to your computer that doesn't get along with Outlook, or your system has a virus. Regardless of the specific cause, there are several key troubleshooting fixes to try that might help.

How to Fix Outlook Not Opening in Windows

Try these troubleshooting steps in the order presented here, from simple to more complicated.

1. Restart your computer. This is a very basic troubleshooting step but you'd be surprised how often it works for issues like this one.

2. Open Outlook in Safe Mode. If the program opens as expected in Safe Mode, the reason it won't open normally is likely due to one or more add-ins.

   Follow these steps to disable add-ins:

   1. Go to File > Get Add-ins.
   2. Select My Add-ins.
   3. Choose an add-in.
   4. Right-click the add-in and select Remove.

   If that doesn't work (every Outlook version is a little different), try these steps:

   1. Select File > Options > Add-ins.
   2. In the Manage section, select Go.
   3. Clear the check boxes next to the add-ins you want to disable.
   4. Select OK.

3. Check Windows for updates. Although this might seem like an unrelated fix, there could be an update pending in Windows Update that is the exact fix you need to make Outlook open again.

4. Scan your computer for malware. If you find a problem, resolve it with your security software, reboot your computer, and try to start Outlook again.

5. Repair Outlook. If the application is damaged, use the built-in Microsoft 365 repair utility to fix it.

   1. Close all Office applications.
   2. Open Control Panel.
   3. Search for and select Uninstall a program.
   4. Right-click Microsoft 365 and choose Change.
   5. Select Online Repair or Quick Repair.
   6. Restart Outlook after the process completes.

6. Repair your Outlook profile. Outlook profiles can become corrupted, causing all sorts of problems, including Outlook not opening.

   1. Select File > Account Settings > Account Settings.
   2. Go to the Email tab and select your profile from the list.
   3. Choose Repair (this option isn't available for Outlook Exchange accounts).
   4. Follow the prompts to complete the wizard and then restart Outlook.

   As you can tell, this step is only useful if your problem is sporadic. If you can't open Outlook to complete this step, move on to the next option below.

7. Repair your Outlook data files. If Outlook still doesn't open, use the Inbox Repair tool to find and possibly fix the problem.

   1. Search your computer for Scanpst.exe (the Inbox Repair tool). Microsoft explains which folder on your computer holds this file.
   2. Select Browse, navigate to your personal folders (.pst) file, choose the file, then select Start.
   3. Select Repair if the scan finds errors.
   4. When the repair is complete, restart Outlook.

   This only works in Outlook 2016 and older. If you're not sure which version you have, go ahead and try these steps.

8. Reset the navigation pane. A startup issue with the navigation pane can prevent some versions of Outlook from opening correctly.

   You can do this through the Run dialog box. Open Run via Win + R, and then execute this command:

   outlook.exe /resetnavpane
   

How to Fix Outlook Not Opening in Mac

The following troubleshooting techniques apply to Outlook 2016 for Mac and Outlook 2011 for Mac.

1. Restart your Mac. Turning your computer off and then on again will flush Outlook from the memory, which is helpful if it won't open because it's hanging in the background.

2. If Outlook opens intermittently, seize the opportunity to check for updates via Help > Check for updates. A recent update could include a fix for the problem. Install any available updates you see.

3. Rebuild the Outlook database. Using the Microsoft utility to rebuild a corrupted database might solve the problem of Outlook not opening on a Mac.

   If you have a Microsoft Exchange account, rebuilding the database deletes any information that isn't synced with the server. Back up any Outlook data stored only on your computer before you rebuild the database.

   1. Exit all Office applications.
   2. Press the Option key and select the Outlook icon in the Dock to open the Microsoft Database Utility. It's also available here: /Applications/Microsoft Office [version]/Office/.
   3. Select the identity of the database you want to rebuild.
   4. Choose Rebuild.
   5. When the process is complete, restart Outlook.