Mac Security · Mac Privacy Controls · Lesson 4 of 5

Sharing Settings You Might Not Need

Set AirDrop to Contacts Only and switch off sharing doors you never use.

AirDrop on a Mac

AirDrop sends photos and files between nearby Apple devices without the internet. It uses Wi-Fi and Bluetooth over a short distance, about the size of a room or two.

It's handy. But it also means someone close by could try to send you something. So the key setting is who may send to you.

To check it, click Control Center in the menu bar, then the arrow or icon next to AirDrop. You'll see a few choices:

• Off: nobody can find your Mac to send to it.
• Contacts Only: only people saved in your Contacts app can see your Mac.
• Everyone: any nearby Apple device can see your Mac and try to send.

You can also set this in a Finder window. Click AirDrop in the sidebar and look for "Allow me to be discovered by".

Contacts Only is the best everyday choice. Your family and friends can still send you things. Strangers on a train, at a cafe or in a classroom can't see you.

Use Everyone only for a moment, for example when a new coworker who isn't in your contacts needs to send you a file. Then switch back.

When something arrives, your Mac shows who sent it and asks you to Accept or Decline. If you don't know the sender, or didn't expect it, choose Decline. Files from strangers can be rude pictures, or a document made to trick you.

Your Mac's name is what others see in AirDrop. If it's something like "Rosa Lopez's MacBook", strangers set to Everyone can learn your name. You can change it in System Settings › General › About.

The Sharing list

Your Mac can open several doors that let other computers reach it over a network. A network is a group of connected devices, like everything on your home Wi-Fi. These doors live in one place: System Settings › General › Sharing.

Most are off when your Mac is new. But you, an app, a past helper or an old job may have turned some on. Here are the ones that matter most.

• File Sharing lets other computers on the network open folders on your Mac.
• Screen Sharing lets someone on another computer see your screen and control it.
• Remote Management is a bigger version of Screen Sharing used by IT teams to look after many Macs.
• Remote Login lets someone sign in over the network and type commands, the same kind you met in Terminal, without sitting at your Mac.

Others include Media Sharing, Printer Sharing, Bluetooth Sharing and Internet Sharing.

Most of these doors ask for a password. Even so, a door that's open is one more way in. If a password leaks or is easy to guess, an open door becomes a real risk, especially on public Wi-Fi.

The rule is simple. Turn off what you don't use. Go down the list and switch off anything you don't recognize or no longer need. You can always turn one back on later.

Two exceptions. If your Mac belongs to work or school, ask IT before you change anything, since they may need these doors to help you. And if you share music or a printer at home on purpose, leave that one on.

Watch for this scam too. A fake support caller may ask you to turn on Screen Sharing or Remote Management. Say no and hang up. Then check this list to make sure nothing was left on.