I’ve noticed on occasion that my Mac’s firewall settings change without my knowledge. This probably occurs when certain Apple apps and programs are updated to new versions or when they are initially installed. I recommend you periodically check these settings to be certain that applications, programs and services aren’t set up to accept incoming connections from the Internet without your knowledge.
Select Apple and then select System Preferences. Next, open Security & Privacy. If you’ve missed my previous two articles, I suggest you stop by the Transcript Bulletin on Main Street and pick up the Jan. 29 and Feb. 5 copies to see how to set up your other privacy settings. You can also access many of my past articles online at www.TooeleOnline.com for a fee.
Let’s go directly to the Firewall tab near the top of the Security & Privacy box. Here, you can easily see if your Firewall is enabled. Go to the bottom-left and select the lock, then enter your Apple ID and password and select Unlock. This way, you can view and make changes to the options in the Firewall tab.
If your firewall is turned off, you should turn it on by selecting the Turn On Firewall button, unless you are running antivirus software that takes the place of your firewall setting. Next, select the Firewall Options button.
In the next box that opens, you have the choice for total protection from incoming connections by selecting the box to Block all incoming connections. In the window below, you’ll see a list of apps and programs that are allowed to accept incoming connections. Personally, I remove everything in the box so nothing is allowed to communicate with the Internet. To remove an item, first select it and then select the “-“ symbol below the box and to the left. Conversely, if you find you need an app to be added to the list so that it receives incoming connections, select the “+” symbol and then select the app from the box that opens and then select “Add.”
There are two more options below to further control incoming connections. The first one will either allow or disallow signed software to receive incoming connections. This is software that has a valid certificate to provide services and needs access from your network. This box can be checked because there are some apps and other valid signed software that requires access from Apple and other important providers.
The next box allows you to enable what’s called “stealth mode.” When you turn on this option, it prevents any unauthorized incoming responses by probing requests sent to your Mac. This is a way to keep your Mac from revealing its existence.
If you want detailed information about these options, I recommend you click the “?” symbol at the bottom-left.
Once you have made your choices, select OK and then close the Security & Privacy box.
For 14 years, Scott Lindsay has helped tens of thousands of people better their skills, publishing more than 300 articles about the computer and the Internet. You can reach Scott for comments or questions at ScottLindsay@Live.com.