Short answer:
Set Microsoft Outlook as your default email app. This ensures that mailto links (e.g. someone@company.com) open in Outlook instead of another email client.
If mailto links open the wrong app, follow the steps below to set Outlook as the default email client on Windows 11 or macOS.
Set Outlook as default on Windows 11
- Open Settings
PressWindows + Ior click the Start menu and select Settings. - Go to Default Apps
Click Apps → Default Apps. - Search for Outlook
Type Outlook in the search bar and select Outlook (desktop). - Set MAILTO as default
Scroll to MAILTO, click it, and choose Outlook. - Done
Mailto links will now open in Outlook.
Test it: Click support@yourdomain.com and confirm that Outlook opens a new message.
Set Outlook as default on macOS (Sonoma or Ventura)
- Open Outlook
Launch the Outlook app. - Open Settings
Click Outlook in the top menu and select Settings. - Go to General
Select the General tab. - Set default email reader
Find Default email reader and select Microsoft Outlook. - Done
Your changes are saved automatically.
Test it: Click support@yourdomain.com. A new email draft should open in Outlook.
Why are mailto links opening the wrong app?
This usually happens when another email app is set as the default. Your operating system controls which app handles mailto links.
- Another email client (e.g. Apple Mail, Gmail app) is set as default
- Outlook was installed after the default was already set
- Default app settings were reset during an update
Troubleshooting
- Outlook is not listed
Make sure Outlook is installed and opened at least once. - Wrong version of Outlook
Ensure you select the correct Outlook app (desktop vs new Outlook). - Still opening the wrong app
- Windows: Reset defaults in Settings → Apps → Default Apps
- macOS: Restart Outlook and set it again as default
