Go to “Reachable At” and check that your Apple ID and mobile number are listed.

Navigate to Apple ID and sign in to your account.

Enter your passcode, then press “Install Now.” If “Download and Install” is displayed instead, press it to install the latest update.

Select the one you wish to install if there are two update options.

Select “General,” then “Software Update.”.

Plug your iPhone into a power source and connect it to the internet using Wi-Fi.

“Upgrade Now” will install the latest Mac operating system. “Update Now” will install the latest update for the Mac operating system installed.

From the “System Preferences” window, click “Software Update.”.

Access the Apple menu and choose “System Preferences.”.

Follow these steps to update your macOS and iOS on your iPhone.

In order for iMessage to function as expected, it needs to be running on an up-to-date OS.

Beneath “You Can be Reached by FaceTime at,” ensure your mobile number and Apple ID are enabled.

Go to “Settings,” then select “FaceTime.”.

This is the ID you’ll need to sign in with when accessing iMessage from your Mac.

At the bottom of the screen, your Apple ID will display.

Beneath “Start New Conversations From,” tap your mobile number, unless you prefer to use one of your email addresses.

Beneath the “You Can Receive iMessage to and Reply From” heading, ensure the mobile number, Apple ID, and email addresses you use to text are enabled.

If “Use your Apple ID for iMessage” displays, select it, then sign in using the Apple ID you used on the device you wish to sync with.

Select “Messages” and ensure the “iMessage” toggle switch is activated.

From your iPhone, launch the “Settings” app.

How to connect mac to iphone messages