Who’s Been Using Your Mac Behind Your Back? Find Out!
Suspect someone’s been using your Mac when you’re not around, even though you told them not to? Find out, without the need for special software.
You could physically dust your Mac for fingerprints, of course, but if you lack the gear for that don’t worry: there are digital tools you can use for this detective work. You’ll be amazed at what you can find out just by checking logs and looking at recently open documents and applications.
Ryan recently showed you how to check if someone’s been using your PC , but it didn’t take long for all of you to ask about doing the same thing on the Mac. Here’s how you can tell if someone’s been using your OS X computer.
Step 1: Check The Logs
Your Mac logs a lot of things. Obsessively. Open up the Console if you don’t believe me – this app gives you a simple way to explore a wide variety of logs. You’ll find it in Utilities, which is in your Mac’s Applications folder. Open it up for the first time and you’ll mostly see gibberish:
It’s almost a record of everything that ever happened on your computer, and it can be completely overwhelming.
So, how does this help you? If you can narrow it down to just relevant points of information, a lot. Perhaps the most helpful thing is to see a list of every time your computer woke up, and doing just that is simple. Type “wake reason:” into the search bar and you’ll see when that happened:
Click the “earlier” button at the bottom to go further and further back into time. You know something might be fishy if your computer woke up some time while you were out of the house.
There’s a quicker way to do this, if you’re comfortable with the Terminal: just type
syslog |grep -i "Wake reason" and you’ll see a longer list:
Knowing when your computer wakes up might not be enough – cats pressing keyboard keys can be enough to prompt this. But if you’re using a MacBook you’ll know exactly when someone opened it to use your computer, and that’s helpful.
This won’t tell you who is using your computer, of course, or what they did. But it’s a good place to start.
Step 2: Check Recent Items
Your Mac keeps track of recently opened applications and documents. It does this mainly to help you quickly access them again, but it’s also really useful if you suspect someone else is using your computer. After all, they’ll probably be interested in different applications and documents than you are.
See a list of all recent applications and documents by clicking the Apple logo at top-right, then hovering over “Recent Items”. You’ll see a list:
Hold Command and you can click to see these files in Finder, giving you access to information like when they were last opened.
Speaking of: newer version of OS X offer similar functionality to this in the Finder itself. You’ll see recently opened documents, pictures, movies and more broken down into categories on the All My Files shortcut:
If you find something here you know you didn’t look at recently, congratulations: you’ve got one more piece of evidence that someone else is using your Mac while you’re not around.
There are other “Recent” things to check, of course, beyond what your Mac records on its own. Your web browser, for example, includes a detailed web history. Applications like Microsoft Word and InDesign have their own list of recently opened documents. Check these and other things if you want to gather further evidence.
Bonus Step 1: Install Snooping Software
If this isn’t telling you enough, and you suspect the unauthorized usage is ongoing, you could install some snooping software to find out what’s going on. Prey lets you monitor computer usage from any other device connected to the web. You can take screenshots to see exactly what’s going on with your Mac while you’re away from it. Heck, you could even use it to take a picture of your moocher, using the built-in webcam.
Alternatively you could just use Chicken of the VNC or any remote software to watch what’s happening on your computer while you’re away.
Bonus Step 2: Kill It With Passwords
But there’s an even simpler solution: lock your Mac with a password. If you don’t want people using your computer behind your back this is the most effective means of doing so.
If you’d rather not do that, however, you should get a pretty good idea of who’s using your Mac with the first two steps – between the logs and the recent apps a decent detective should be able to rule out most major suspects. The rest, of course, is up to you – unless you use Prey to capture a picture of the culprit.
If you have the same concerns about your phone, check out these apps that can catch snoops trying to get into your phone.
I want to know which tools you think are most useful for this job, and which have worked for you. Share your battle stories in the comments below.
Image Credits: Willow and the Mac Via Flickr
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