Cortana is a digital assistant in windows 10. She will not listen your voice command until you click on search box, because she is not always in listening mode. You can put her on listening mode and make her active to perform your task by saying Hey Cortana.
There is some steps to activate Hey Cortana:
Click on search box placed on next to start button, she will say hello to you.
Click on the settings button which is located above the start button in the left side.
Here is a option Let Cortana respond to “Hey Cortana”, switch on it.
Also, you can activate to Cortana by keyboard shortcut Win key + C.
Now you can give your instructions to the Cortana any time, and she will perform on your task according to your instructions and give you the result.
Before activating the Cortana, you should check the microphone of your PC whether the microphone is designed for Cortana or not.
Because you can give your direction to Cortana, only when the microphone will support the Cortana.
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