I assume you mean that when you double-click the .eml file, it opens with Outlook? You need to set eM Client as the default program to open .eml files within Windows 10. To do this, in windows:
- Go to ‘all settings’ in windows
- Select ‘default apps’
- Select ‘default apps by type’ at bottom of page
- On the left side pane, select ‘Em Client’
- Select ‘Choose defaults for this program’
- Check the ‘Select all’ box
Now, when a .eml file is double-clicked, it should open with eM Client.
Thank you. Worked a treat