

It may also be that your devices are not up to date - make sure to update your Mac and the device you're AirPlaying to. If things still aren't matching up, access your computer's Firewall by opening System Preferences, going to "Security & Privacy" and selecting "Firewall." Make sure the "Firewall" is turned off. If you're trying to connect to your iPad, you also need to be logged into the same Apple ID account. When attempting to use AirPlay from a Mac to an Apple TV or other AirPlay-compatible device, the most common misstep is not having both devices connected to the same Wi-Fi network. You can also click "Use As Separate Display" to have your Mac screen cast its screen to your other device, rather than both devices displaying the same screen. Click the AirPlay icon in the menu bar and in the drop-down, select "Mirror Built-In Retina Display" to have your other device match what's on your Mac desktop. Quick tip: You can change how your Mac display is mirrored to another device.

Click the drop-down next to “AirPlay Display” on the Displays page.Next, choose Screen Mirroring, then select your Apple TV.

To AirPlay Mirror from your Mac, click on the Control Center icon at the right side of your Mac's menubar. Click “Displays” in System Preferences. Click on your Apple TV from the dropdown (if you have multiple Apple TVs in the vicinity, choose the one you want to use right now).
