How to Set Outlook as Your Default Email Client

Setting Microsoft Outlook as your default email client ensures that all mailto links, .eml files, and email-related actions open in Outlook instead of the Windows Mail app or another email program. This takes under a minute to configure in Windows Settings. For setting up your first email account, see our Outlook email setup guide.

Key Takeaways

• On Windows 11, go to Settings > Apps > Default apps, search for “Outlook,” and click Set default to make it handle all email-related files and links.
• Configure the MAILTO protocol separately if mailto links still open in the wrong app — find it under Default apps > Choose defaults by protocol.
• You must open Outlook at least once before it appears as an option in the Default Apps settings.

How Do I Set Outlook as Default on Windows 11?

Open Settings > Apps > Default apps, search for “Outlook,” click on it, and click Set default — this assigns Outlook to handle all email file types and the mailto protocol.

Quick Method (Set Default Button)

1. Press Windows + I to open Settings.
2. Click Apps > Default apps.
3. In the search bar, type “Outlook”.
4. Click Outlook in the results list.
5. Click Set default at the top.
6. Outlook is now the default for MAILTO links, .eml files, .msg files, and calendar invitations.

Manual Method (Per Protocol/File Type)

If the Set default button does not appear or you need to change specific associations:

1. Open Settings > Apps > Default apps.
2. Search for “Outlook” and click on it.
3. Scroll through the list of file types and protocols:

File Type / Protocol	What It Handles	Click to Set
MAILTO	Email links on web pages	Select Outlook
.eml	Email message files	Select Outlook
.msg	Outlook message files	Select Outlook
.vcf	Contact card files	Select Outlook
.ics	Calendar invitation files	Select Outlook
.vcs	Calendar event files	Select Outlook

1. Click each entry and select Outlook from the list of available apps.

Classic Outlook vs New Outlook

Windows 11 may show two Outlook entries in Default Apps:

Entry	App	When to Choose
Outlook	Classic Outlook desktop	Full-featured, IMAP/POP3 support
Outlook (new)	New Outlook for Windows	Cloud-first, modern interface

Choose the version you primarily use. If you switch between both, set the one you use most frequently as the default.

How Do I Fix Mailto Links Not Opening in Outlook?

If clicking a mailto link on a website opens the wrong email app, configure the MAILTO protocol directly in Windows Settings or through the browser.

Fix in Windows Settings

1. Open Settings > Apps > Default apps.
2. Scroll to the bottom and click Choose defaults by link type (or Choose defaults by protocol).
3. Find MAILTO in the list.
4. Click the current app and select Outlook.

Fix in Chrome

1. Click a mailto link — Chrome may show a popup asking which app to use.
2. Select Outlook and check Always use this app.
3. If no popup appears: go to chrome://settings/handlers and set Outlook or remove other handlers.

Fix in Edge

1. Go to edge://settings/content/protocolHandlers.
2. Remove any email handlers that are not Outlook.
3. Click a mailto link — Edge should now prompt you to select Outlook.

According to Microsoft Support, Outlook must be opened at least once before Windows recognizes it as an available default email handler.

How Do I Set Outlook as Default on Windows 10?

The process is similar to Windows 11 but uses a slightly different Settings layout.

1. Open Settings > Apps > Default apps.
2. Under Email, click the current default app.
3. Select Outlook from the list.
4. For calendar defaults, scroll to Calendar and select Outlook.

Alternatively: 1. Open Control Panel > Default Programs > Set your default programs. 2. Select Microsoft Outlook from the list. 3. Click Set this program as default.

How Do I Set Outlook as Default on Mac?

Open Apple Mail, go to Preferences > General, and change the Default email reader dropdown to Microsoft Outlook.

1. Open Apple Mail (even if you do not use it).
2. Go to Mail menu > Preferences (or Settings on newer macOS).
3. On the General tab, find Default email reader.
4. Select Microsoft Outlook from the dropdown.
5. Close Preferences.

Alternatively, if Apple Mail is not installed: 1. Open Microsoft Outlook. 2. Go to Outlook menu > Preferences > General. 3. Click Make Default next to “Default email application.”

Why Is Outlook Not Showing as a Default App Option?

The most common causes are Outlook not being installed, never opened, or a corrupted registration — reinstalling or repairing Outlook fixes most cases.

Troubleshooting

Issue	Fix
Outlook not in Default Apps list	Open Outlook at least once, then check again
Only “Outlook (new)” appears	Classic Outlook may need repair: Control Panel > Programs > Repair
Set default has no effect	Restart Windows after changing defaults
Mailto still opens wrong app	Set MAILTO protocol individually (see above)
Multiple Outlook versions	Uninstall the version you do not use
Managed by organization	IT may enforce defaults via Group Policy — contact IT

Re-Register Outlook

If Outlook is installed but does not appear as an option:

1. Open Command Prompt as Administrator.
2. Run: "C:\Program Files\Microsoft Office\root\Office16\OUTLOOK.EXE" /regserver
3. Wait for the command to complete (no output is normal).
4. Check Default Apps again — Outlook should now appear.

For more Outlook configuration, see our Outlook signature setup guide and Outlook rules setup guide. If you need Outlook desktop, Microsoft Office 2024 Professional Plus ($199.99) includes the classic Outlook application.

Frequently Asked Questions

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