OS X (formerly Mac OS X) is the marketing name for Apple's computer OS. Note the proper pronunciation is "ohh ess ten" and not "oh ess ex". it is be replaced by macOS to match its the format of watchOS, tvOS, and ios.

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53
votes
11answers
59k views

How can I figure out what's slowly eating my HD space?

Every few days I get notices on my MacBook that it's running or run out of hard drive space. Curiously, restarting the computer will enable me to recover gigabytes of space (this past time, it was ...
48
votes
4answers
98k views

How do I disable System Integrity Protection (SIP) AKA “rootless” on OS X 10.11, El Capitan?

Apple has introduced System Integrity Protection, also known as "rootless", with OS X 10.11, El Capitan. I understand this is a step for general protection against malware but as a developer I need ...
175
votes
5answers
58k views

“File Open” dialog is missing sidebar items

I'm having the strangest issue since updating to OS X El Capitan. My "Open File" dialogs show the sidebar but all my main (and useful) locations are missing. Take a look at this screenshot. This ...
65
votes
7answers
39k views

Isn't Inactive memory a waste of resources?

I'm looking for explanation of memory usage on my machine especially in light of the example in this screenshot below: I understand what is Free and Active means But what are the meanings of Wired ...
26
votes
6answers
15k views

Can I create a shortcut to open a specific application on OS X?

I want to create a keyboard shortcut to i.e. open Firefox while I am working in another application. I know I can use ⌘ CMD+T when I am in Firefox to open a new tab. I haven't found a way to create ...
10
votes
7answers
30k views

How can I get back a system file after deleting it from my Mac?

I've deleted a system file from my Mac and need to get it back. System files can include: hidden files in the root of / - especially unix files in /private /System files /Library files /...
141
votes
23answers
39k views

Is there a quick way to lock my Mac?

On Windows you can hit the keys Windows+L to lock your computer if you step away. I don't want to have to remember if sleep currently asks for a password, if there is a time out where my screen isn't ...
30
votes
5answers
27k views

How can I run/stop/relaunch an application automatically, at boot/login/some other time?

How do you make a script or app to run or stop running automatically when the system is booted, a user logs on, at a specific time, when a disk is attached, etc.?
25
votes
6answers
37k views

Resizing or expanding a CoreStorage volume

I bought a new SSD with 750 GB and made two partitions: 600 GB and 150 GB. The smaller one was thought to be a Bootcamp partition one day, but to date it was just another unused partition. When I ...
159
votes
3answers
92k views

What is the “rootless” feature in El Capitan, really?

I have just learned about the "Rootless" feature in El Capitan, and I am hearing things like "There is no root user", "Nothing can modify /System" and "The world will end because we can't get root". ...
59
votes
7answers
71k views

Is there any way to set a MacBook Pro to not sleep when you close the lid?

The most common use case I have for this is when I'm playing music over AirTunes, but don't want an open laptop laying around. Or when I'm syncing or downloading something. This isn't the same as ...
8
votes
3answers
4k views

What is a Kernel Panic and what does it mean?

I have this report: Anonymous UUID: 84DCCF22-1516-5255-9602-7222ECDA9095 Tue Aug 11 20:26:13 2015 *** Panic Report *** panic(cpu 2 caller 0xffffff8028bc1cde): "launchd died\nState at Last ...
54
votes
4answers
14k views

How to add characters to the press and hold character picker in OS X Lion?

In OS X Lion, there is a very useful feature for people like me who need to write in multiple languages, which pops up a small menu of additional characters when you hold down a letter. For instance, ...
462
votes
137answers
301k views

Please share your hidden OS X features or tips and tricks

Do you know any hidden or little-known nice feature of Mac OS X? It doesn't matter what it is—maybe just a short terminal command or a keyboard shortcut. Share your experiences on hidden Mac OS ...
21
votes
3answers
83k views

How can I get admin access to a Mac without knowing the current password?

My Father died last year and I inherited his Mac Mini. My wife has retired and we are trying to set up the mini for her use but the changes we want to make require admin access and we do not have the ...
6
votes
3answers
33k views

Terminal returns not found for most commands Mac OSX

I'm really new to Mac OSX and UNIX based systems. I wanted to run a few Windows games on my Mac Mini so I started installing Wine and MacPorts. Having done so, I typed in sudo port install wine and ...
43
votes
5answers
12k views

How do I remove duplicate “Open With” context menu items in Finder.app?

For whatever reason, the "Open With" context menu in Finder is always listing every app four times (exactly). I've read about (and tried) rebuilding the Launch Services database to restore the ...
27
votes
6answers
29k views

How do I write to NTFS drives in OS X?

What is the best, easiest, preferably cheapest way to make OS X write to NTFS-formatted drives in Mac OS X?
24
votes
6answers
268k views

Can I downgrade to Mavericks after installing Yosemite (beta/developer preview)?

I have installed the developer preview for Yosemite. Huge mistake. Everything in my workspace is broken. I don't have any sort of backup image. I was wondering if I could re-download Mavericks and ...
351
votes
7answers
261k views

How do I recompile Bash to avoid Shellshock (the remote exploit CVE-2014-6271 and CVE-2014-7169)?

Given that Bash 3.2 (the version shipped by OS X) is vulnerable to the remote execution exploit known as "Shell Shock" (CVE-2014-6271 and CVE-2014-7169) how do I rebuild Bash and secure my system ...
33
votes
5answers
15k views

On OS X, what files are excluded by rule from a Time Machine backup?

In addition to whatever files I may choose to exclude, what files does the system exclude by rule or classification? It might make sense not to backup Trash or Caches, but I'm looking for a way to ...
14
votes
5answers
21k views

Create global shortcut to run command line applications

What steps do I need to run a command line program via a global shortcut? I setup Automator to create a new Run Shell Script and tried to assign a shortcut in System Preferences -> Keyboard -> ...
195
votes
4answers
62k views

How can I disable animation when switching desktops in Lion?

I would very much like to disable the sliding animation that occurs when switching desktops via ctrl+→/← or ctrl+[number] in Lion. This was previously accomplished in previous versions ...
70
votes
9answers
101k views

Why are dot underscore ._ files created, and how can I avoid them?

I am using different operating systems on different machines on different locations. I am using a USB flash disk to keep my files (source codes etc.). I am new to Mac OS X and now I realize there are ...
28
votes
8answers
3k views

How do I uninstall a program completely on a Mac?

I come from a PC background... every time I want to uninstall an application, I must use add/remove programs. On the mac, you can simply run a .app file from wherever you want, and many say that the ...
182
votes
239answers
39k views

Which OS X Applications do you find indispensable?

Please Search Prior To Posting! There are many applications already listed. In all likelihood, this includes the one you are thinking of. Please check the existing answers to avoid duplicates, and ...
22
votes
3answers
3k views

Why is /tmp a symlink to /private/tmp?

Why is /tmp a symlink to /private/tmp on Mac OS X? In other words, why isn't /tmp just a regular directory, like on Linux or BSD? I understand how it works and I don't mind it, I'm just interested in ...
21
votes
4answers
176k views

Roll back from OS X Mavericks ( or any newer OS) to Mountain Lion

I installed the developer preview of OS X Mavericks, & too many things broke. I can't stay on it & need to roll back to Mountain Lion. Any ways of doing that? Please help! I originally ...
13
votes
1answer
3k views

Why does the version of Java verified by Oracle differ from the version shown at the command line?

Questions Why do versions differ? Should we trust Oracle's verification routine? In some cases, the version verified by Oracle is different from the version shown at the command line. Example ...
35
votes
4answers
6k views

How can I prevent iPhoto from opening everytime I plug my iPad/iPhone?

How can I prevent iPhoto/Photos/Image Capture from launching everytime I plug in my iPad/iPhone?
5
votes
4answers
18k views

Completely synchronise multiple Macs

I actually have a Macbook Pro with Snow Leopard (I plan on upgrading to Lion). I may have to buy an Mac mini in order to have a full dual screen (external identical screens) layout (see my previous ...
406
votes
133answers
212k views

Got any tips or tricks for Terminal in Mac OS X?

One tip or trick per answer. My favorite is open . Opens the folder you're currently browsing in Finder. You can also pass URLs, images, documents or else to open. If you specify a program name ...
167
votes
107answers
53k views

What tiny thing in Lion makes you smile or has caught you off guard?

I would like to call for a place to list some little things that surprise you about Lion. There are so many articles and lists of all the new features with information overload, I would rather focus ...
116
votes
8answers
383k views

How can I manually delete old backups to free space for Time Machine?

I use a Time Capsule for backup and now I want the drive to back up data from an extra Mac. But the drive is filled up with old backups from Mac 1. There simply is not enough space available for the ...
63
votes
14answers
115k views

DNS not resolving on Mac OS X

Some of my coworkers are having troubles on their Macs - DNS resolution does not work under Mac OS X. They're running Snow Leopard 10.6.8. They can use DNS in a Windows 7 virtual machine (VMware ...
29
votes
4answers
34k views

Do MacBooks have a true “Hibernate” option?

I've recently switched from Windows to a MacBook pro. In Windows, there are the following shutdown options: Standby - the machine goes into a "light sleep" from which it can awaken very quickly (...
20
votes
6answers
9k views

How can I expand the number of special characters I can type using my keyboard?

I am aware that when I press ⌥ or ⇧⌥ on my Mac, I can type a variety of special characters. I also know that I can insert special characters using the character palette. Is there a way to expand the ...
28
votes
3answers
9k views

Optimize macbook pro for internal SSD+HDD drives

I upgraded my MacBook Pro by replacing the SuperDrive with an SSD. I'm now using the SSD as the boot volume and have all my applications. My home folder is on the HDD. My question is how to best ...
19
votes
1answer
4k views

Is there console mode in Mac OS X?

Is there something like Linux console in Mac OS X? Like "terminal", but without running graphics environment.
3
votes
2answers
2k views

How do I install Windows 10 on MacBookPro5,1, with no optical drive (SSD+HDD)

I have a huge problem. I am not able to install Windows 10 on my late 2008 MacBook Pro with bootcamp. I have replaced the optical drive as it was not working with a 1 TB HDD and i have a SSD drive ...
3
votes
1answer
3k views

iTunes: Moving iTunes Files (Self Managed)

I'm trying to move all my music to another drive and I don't let iTunes organize my music for me. I moved the "iTunes" folder to my external and I also moved my Music folder which is also outside of ...
37
votes
6answers
21k views

How can I modify the list of Applications under 'Open With…'?

I recently went to open an audio file, and wanted to open it in an editor instead of a player. I right-clicked it, hovered over 'Open With...' and was met with a very unsightly list. I have seen a ...
52
votes
10answers
62k views

OS X computer name not matching what shows on terminal

My computer name in System Preferences > sharing is set to "archos" but is showing as "iphone" on the terminal. It just started doing this after I loaded Xcode for doing iPhone development. Last ...
60
votes
6answers
19k views

How can I activate buttons with just the keyboard?

Many user interface (UI) elements or dialog boxes have buttons. I would like to be able to activate a button with just the keyboard, without the mouse. How can I do this?
28
votes
9answers
120k views

Unable to Resize Partitions

I have recently created a partition on my macbook air running OS X 10.9, and this was to run install another OS instance (Yes, OS X 10.10 Yosemite, but that is an aside to the query I have) on it. I ...
17
votes
2answers
7k views

Can you make OSX mount just certain partitions when you connect an external HDD?

I have an external HDD with 4 partitions. My question is the following: is there a way of telling the OS to mount just two of them (One FAT and one HFS+) when I connect the HDD? It is rather annoying ...
6
votes
5answers
190k views

How do I create a Mac bootable USB drive using Windows?

My MBA 2012 with OS X 10.9.4 Mavericks won't boot anymore - it simply freezes after the initial jingle. I already tried resetting NVRAM and SMC, but to no avail. I don't have any time machine backups. ...
103
votes
53answers
19k views

What features of Mavericks are beneficial to you?

This question serves to share and collect the enhancements that make a large difference to how you use your Mac. Please post one feature per answer. Please also check to see if your answer has ...
106
votes
8answers
65k views

How to simulate slow internet connections on the mac

What's a good software solution to slow down internet connections on the mac for testing and simulations? My primary need is when testing code in the iPhone / iOS simulator, so slowing down the ...
55
votes
16answers
46k views

How do you maximize windows?

Unlike Windows, you cannot maximize a window in Mac with a click of the button. The little green (+) button next to the red and yellow buttons at the left of the windows does some strange stuff ...