Open Opera browser on your computer. As you can see Google has been set as your default search engine. Click on the opera icon at the top of the browser. Hover your mouse on the settings tab and select “Preferences.” Preferences dialogue box will appear. Click on the “Search” tab. Select Bing in the list. Click on Edit button. Now, Click on the Details Button. Select the check box ” Use as Default Search Engine”. Also Select the check box ” Use as Speed dial Search Engine” to use Bing as the speed dial search engine. Click ok to save the changes. As you can see Bing is now set as your default search engine.