Ask Different is a question and answer site for power users of Apple hardware and software. Join them; it only takes a minute:

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

Is there any way to disable the "the disk was not ejected properly" message?

I use a KVM and need to switch between two systems and have a memory stick that is in the KVM. The problem is that it's very annoying to get the message every time I switch from one computer to the other. I know, I can unmount it (and probably should), but I switch all the time, so it's a inconvenience to unmount, and there is nothing sensitive on the memory stick.

share|improve this question
Sorry, I have no answer. However keep in mind, that message is to remind you that data is held in memory and not yet written to the disk. Which is particularly important when you switch often. – DerMike Jan 7 '11 at 14:01
I've done this a long time and I have never lost anything. I'm not saying it won't happen, but I'm willing to take the risk. – Sindre Sorhus Jan 7 '11 at 15:19
Okay, I have to ask: anyone know why we got three near-identical questions within 10 hours—this one, 6090, and 6108 (and yes, the latter two have been closed as dupes). – Dori Jan 8 '11 at 1:38
@Dori It's the time after Christmas, so new Macs or Cameras with SD Cards :) Although I would like to point out that my question specifically was asking about the Write Cache, which is what the warning is usually about (ignoring issue like Symlinks/open system files on the drive) – Michael Stum Jan 8 '11 at 7:08
I hear what you are saying, that you would rather take the chance on losing the memory stick, I just thought I would let you know that it does happen; I found this forum because I didn't eject my memory stick before disconnecting and wasn't able to access the 1.8gb worth of movies that I just took. Luckily Disk Utility was able to fix it, this time. – cate Jan 8 '11 at 14:09
up vote 15 down vote accepted

Much better to do this:

sudo launchctl unload -w /System/Library/LaunchDaemons/

Which will just stop the UserNotificationCenter service from running, leaving your system files intact!

beware: as noted in the comments, this will disable all system notifications, including those when programs request access to system services like contacts

share|improve this answer
Will it continue to be unloaded after restarting my Mac? – Sindre Sorhus Apr 23 '11 at 15:39
Unloading a launchctl plist persists across restart, so I believe so. That said, I hardly ever reboot, so haven't tested it yet! – James Apr 23 '11 at 19:15
(I rebooted, and it has persisted fine :) – James Apr 29 '11 at 10:27
That solution has a negative side effect: It will also hide those "xy-application would like access to your contacts" popups. To revert it: sudo launchctl load -w /System/Library/LaunchDaemons/ – user52466 Jul 2 '13 at 1:08
Yeah this is very dangerous. It will most likely stop you from getting notifications from the system. In 2011, notifications were not a big deal but they kind of are today in 2015. – alp Feb 10 '15 at 1:32

Certainly not an elegant answer but, you can disable found in /system/library/coreservices - replace it with another app or file with the same name. It will stop any warnings popping up (including that your drive is full) so watch out for that, but in my experience it does what you are looking for.

I actually did this to my mac a long time ago, and forgot about it until you asked you question. Credit to Macpadawon at for the answer - same place I found my answer a couple of years back.

share|improve this answer
Wow. Nice catch. I certainly wouldn't do this to my own system, but it's nice to know it can be done. I suppose the app could be replaced with an empty file. – Harv Jan 18 '11 at 1:42
I've done it on three different macs with no issues, although most of the time I just unmount things as well. – Ciaocibai Jan 18 '11 at 22:23
At least you did not notice any issues, right? Sorry, couldn't resist. :-) – DerMike Jan 21 '11 at 11:20

Ok. The issue with flash drives or other USB drives is this; whenever you write data to a drive... ANY drive on your system, the data is first written to a buffer in memory. Later, when the computer gets around to it, it will flush the buffers to the device (hard drive, SSD, or any USB device). That may be instantaneous (at least to us mere mortals) or it may take a few seconds. The possible delay means that if you yank a USB device before the buffers have flushed (or the fluffers have bushed) you may end up with a corrupted drive, or a set of corrupted files on the drive.

For those in the know, if you only read from a device, then there is NO NEED to flush the write buffers before you yank to your heart's content. So... The annoying MAC OS X warning is most probably NOT relevant to most users. Especially if you are only reading from the USB device.

If you happen to write to a USB device, the odds of the system not completing a buffer flush before the hardware is yanked, is very small.

Therefore Apple NEEDS to provide a way to disable individual messages for power users. Don't treat everyone as a n00b who can't be relied on to know how their computer works.

But... welcome to the "walled garden". If you are a power user using a Mac, well, you just get used to the various, myriad annoyances that you have no control over. If you want a POSIX-based OS and full control, I'm not going to offer any suggestions...

Charlie74. I disagree. While my answer may ramble a bit, it is an explanation of why the message happens. To your point that an answer has been given, I must disagree. Disabling the entire notification subsystem is NOT an acceptable solution, just as removing the battery from your cell phone is NOT an acceptable solution to receiving too many telemarketing calls. The notification subsystem is important and should not be disabled just because the OP finds one of the many myriad of messages to be annoying.

share|improve this answer
So, I'm not sure this ramble really qualifies as an answer to the question... however an answer was already provided that does exactly what you are rambling can't be done - the messages can be disabled. However, as this does not attempt to provide any answer to the question, I'm going to flag this for deletion. – Charlie74 Jan 4 at 23:54
@Charlie74 It's an attempt to make a point, so I'm not deleting it. I will edit out the vague chit chat towards the end. If OP wants to be clear, feel free to provide a positive explanation of why OS X is POSIX certified - and not POSIX-based. – bmike Jan 12 at 17:35

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.