To set Opera
as Default browser, simply open it.
- Click the Menu button (big red button) > Settings > preferences (CTRL+F12)
- Go to the "Advanced Tab"
- Scroll to the "Programs" section
- Activate the "if Check Opera is default browser on startup"
- Click on the Details button, will allow you to configure the type of files that can be handled by the browser.
- Restart Opera.
- You shall get a message asking you if you want to set Opera as the default browser, simply click on the "Yes" button.