The disk was not ejected properly. If possible, always eject a disk before unplugging it or turning it off.

This problem has plagued me for more than a year now. I finally bought a new USB Hard Drive -- and no problem any more. Looks like the old disk had got corrupt somehow and Mac OS lacked the tools to fix it.

this also happens to me when I take the charge plug off the Mac Air. It then says..disk...

Does this help? Change power supply triggers the "this disk was not ejected properly"

SS

Could this have something to do with iTunes? It's been pestering me for weeks, and I have used both external HDDs and memory sticks in a major effort to repair iTunes.

Have you had something plugged in via USB, with a song, playlist, iTunes Library.xml on it?

dw32

I woundn't try, but l want to sell my SG 500G Hard Drive, and buy a new.

What confused me is, when I use Time Machine last years, even I do a lot of operation in my MacBook, the backup will finish perfect. But now, I have to do Nothing when I need to backup my MacBook, even then, the erro will appear sometimes. It so afflictive! Then, I don't know what time the problem first happened actualy. But Updates seems do nothing.

OS 10.9.2, with no Hubs, Just one connection.

HI!

I have the same situation, I get the message "The disk was not ejected properly. If possible, always eject a disk before unplugging it or turning it off."

The same thing happens with diferente external HDD connected by thunderbolt or USB 3.0!

I use some times an External HUB, but just for USB 3.0, but it happens more on thunderbolt connection, since it is the most used.

Does anyone know if it Is a faulty port or a computer hardware problem?

Thank you.

David G.

HI,

Looking at most of the thread it does not like a device numbering issue.

For example devices that have drives can be accessed in System Preference > Network.

Firewire can show up as can Thunderbolt connections.

These two tend to use IP addresses to number devices.

Firewire can be connected to a MIDI device and an old style external iSight Camera that don't get IP addresses but are numbered by the system.

USB also numbers devices so that the system can keep track of them.

A PRAM/NVRAM reset may help.

Hold down the ALT+CMD+P+R keys at a computer restart until you have heard a total of three Start up Bongs.

8:26 pm Saturday; August 30, 2014

This just started happening to me recently with an up-until-now perfectly fine 3 TB Verbatim disk I bought to replace an older drive that wouldn't work with Time Machine. So the Verbatim disk is, I believe... A little over a year old, now? I'm using it with a 15" MBP which is I think 2 years old? Anyway, it worked fine up until about a month ago, at which point it randomly started doing this while the machine was asleep. It only happens during sleep and I can't see anything that triggers it. And here's the other weird thing: Once it has happened, I can't get it to see the drive again with that same USB port until I reboot. It'll see it from the other USB port, but not the one it gave the error on. What I don't know is if that USB port stops working altogether. Haven't tried it yet. Usually I'm too annoyed and I reboot and immediately start a disk repair. I don't think to start plugging other things in. The USB port I'm using is the one on the right, beside the HDMI port.

Hi,

I would use the System Info (System Profile ) in the Apple icon menu top left of the Menu Bar.

You may need to hold down the ALT key to see Alternatives to the Menu items.

You will need the app to display Hardware and the USB subset.

Some of these "hubs" are internal to the computer.

From there you can see from my pic that some items are then on obvious external ports (iPhone on the top bus and the Passport Drive on the second) as well as dealing and linking to internal items like the camera, BlueTooth and Card Reader etc.

ON a Laptop the keyboard and trackpad may also be connected via USB.

If the physical port on the outside of the computer is the issue it might just be due to an external device being plugged in and out regularly.

The Internal items might hint at a USB controller/Bus being at fault depending what is effected.

The external port on one side might be an issue with Blue Tooth and any card reader or the IR Controller that don't work.

8:01 pm Wednesday; September 24, 2014

I had this happening with a drive attached to our small server (running off of an older iMac). The external FireWire drive I use to keep it backed up kept dismounting on its own. Turned out the FW cable was no good. As soon as I used a new one, the problem stopped.

RE: New Mac Pro (late 2013) with LaCie externals: 2x3TB, 1x1TB (USB3), and 2x12TB LaCie 2BIG (each RAID 0 on Thunderbolt 2).

The 12TB drives were behaving perfectly when brand new (about 3 weeks old now). Then, Final Cut Pro with a certain MOTIONVFX.com plug-in occasionally caused my system to crash and reboot automatically. 😟 As a result, finder prefs (minimally) got corrupted and I couldn't even dup or delete a file or folder. PLUS, eventually, the 12's would no longer sleep with the computer and then get ejected when the Mac slept for an extended period of time and when the Mac woke up, it produced the dreaded, "DISK NOT EJECTED PROPERLY" message for BOTH 12's.

I tried everything: zapping PRAM, resetting SMC, rebooting, repairing permissions...Nothing worked. LaCie: No help, although they offered to send new Thunderbolt cables.

I had the same drive-not-sleeping problem with my Mac Mini for a while, and that inexplicably went away recently.

Sooooo... Here's how mine got fixed. Hope it works for you...

Last night there was a car accident (somewhere) at 2:45AM and for 2-1/2 hours we had a power outage in the entire area. At 6AM I woke the computer and the drives were once again working perfectly (and not getting improperly ejected).

The one thing I hadn't tried was shutting down the Mac PRO for an extended period (probably the same extended period of simple sleep that caused the ejection). The Mac Mini's drive-sleep problem probably also went away when it was powered down recently for lack of use.

So try it: Power-down for at least 2 hours.

∆

Interesting.

There used to be a little trick when Firewire devices could not resolve the item count which involved shutting down the computer for about 15 mins.

This was long enough to charge left in the system to drain so that the Firewire ports were effectively reset.

8:59 pm Monday; October 20, 2014

I have been experiencing this since Yosemite update. I sat on the phone with Seagate who said it's a Yosemite problem, so I started a case with Apple. After multiple tests they believe one of the ports is bad and for me to take it to the store. After 1-1/2 hours at the Apple store it is not the USB port and got the same message on one of their computers using my drive. The "genius" says it must be the USB cable. He gives me a new one and I bring it home only to hook it up to the drive and get the same message the next day. I am nowhere for over 4 weeks!

Improper Disk Ejection has been a problem for a while. I have Snow Leopard and Mountain Lion through Yosemite installed on my system. I have an external 3TB HD connected via a CalDigit USB3/eSATA card. No improper ejections EVER occur in Snow Leopard. Improper disk ejections ALWAYS occur with the later OSes. My solution for now is an app called Mountain from http://appgineers.de. The main problem I have found with it is that you have to quit Mountain if you are running an OS Installer app or creating an installer on a flash drive using DiskmakerX, because it seems to interrupt whatever mounting and unmounting of resources the installers do. However, I have not had an improper disk ejection since I installed it on the ML, Mavs and Yosemite drives.

I experienced the same issue with my iMac mid 2011 or 2012 and external HDD 1TB...

thanks to the guy, who mention about different USB ports!

I had this issue when I connected my HDD to the keyboard USBs... but when I connected this directly to the body's USB - suddenly it started to work fine!

I guess, USB ports of the keyboard do not have enough "power" (voltage or how it is called...) to supply HDD, that is why it constantly drops connection...

My advice is: try to connect your external HDD directly to body's USB of your PC, and see, if it helps!

Love and peace to everybody!

Well, it's nearly two years since you wrote that w_clark, did you ever get a resolution? Ive been having the same problem for a year now and have posted two or three times. External hard drives, external CD/DVD player/writer and GPS device, they will mount for a split second then automatically dismount, mount, dismount, and so on adinfinitum, and it is hopeless trying to copy music CDs to iTunes, update my TomTom GPS and make backups. My iMac is on Yosemite and I religiously install OS X updates.