Q: Mountain Lion improperly ejects external disks

@AMCarter3  You might want to consider the 4th recommendation I added to the Cardano procedures: installing Jettison, available at the AppStore.

Jettison runs into a catch-22.  I have my iTunes library on my external USB3 drive on my 2013 Macbook Air.  If iTunes is open, Jettison can't eject the drive, but OS X still seems to manage to unmount it, and leave me in the lurch.

I think there are surely multiple problems being discussed in this thread.  Some folks are really losing, as their drives are unmounting in the middle of disk activity.  For them, I suspect the drive is close to drawing too much USB power and may be causing the USB port to shutdown to protect itself.  Hence, using a powered hub should help.

But there are others of us who only suffer from our drives being mysteriously unmounted when sleeping, despite telling the Energy preferences to _not_ spin down drives, and despite using an external owered hub.  In this case, it appears that something in OS X is either ignoring that preference, or the drive firmware is misinterpreting a "sleep" command as an "unmount" command.

There does seem to be a common thread about USB3 and Air.  And I wonder if "power napping" might be at fault.

I posted earlier in this thread about having the same problems. I had to reformat a server and reinstall everything because this kept happening during Retrospect backups and eventually damaged the startup disk because I had to do hard reboots.The only way I have resolved it is to quit using USB drives. I now use Firewire 800 Lacie drives (rugged portables) and do not have the problem.

As long as there have been USB ports on Macs that I can remember, the devices have randomly lost their connections. Whether keyboards, mice, zip drives etc. You would like to believe that with the plethora if USB drives out there that this would have been resolved but obviously has not.

I know that there have been a few comments about drives other than USB but I think the majority of these problems are USB based. It is not a reliable interface (on a Mac) for drives that have to maintain a constant connection.

Just my two cents - Sorry, I wish had a better solution. If you can afford to get Firewire or maybe Thunderbolt drives, I would suggest it.

Dave.

This is the first time I've heard of Jettison (by St Clair software). Very interesting idea. I know the developer -- he does great work. His "Default Folder" is  my #1 most valued utility app. Have others on this forum tried Jettison for elimiminating this irritating ejection error message issue?

Hi,

I have a lacie rugged thunderbolt with USB 3 and a imac míd 2011, and the ejects only occured with the thunderbolt Port. Not on the USB , in USB mode works fine in ósx ML.

BEST REGARDS

I've got the same lacie rugged thunderbolt with USB 3 this year. Ejections only occurred with the USB port.

I really appreciate Noula's suggestion to install Jettison. Since doing this two days ago, I have not seen the infamous "improper ejection" error message. Jettison seems to  do, automatically without any effort on my part,  exactly what the developer says: "Jettison eliminates the hassle of manually ejecting external drives  before you put your MacBook to sleep and remounting them when it wakes."

By automatically unmounting my two external USB drives when the computer goes to sleep, Jettison is  eliminating the opportunity for Apple's faulty USB power management system to improperly eject my external drives. As soon as my computer wakes up, Jettison quickly remounts the external drives. And, most importantly,  Jettison  has NOT caused any conflict with my Time Machine backups or my SuperDuper clone backups (three of which are scheduled to run automatically at 1:00am every night.

See: <http://stclairsoft.com/Jettison/index.html>

So I had a similar problem. It would eject randomly. Sometimes after 2 mins, and eventually almost immediately after hooking up the hard drive. I tried using the Seagate dashboard, but it was useless. Only allowed you to manage social sharing settings.

The first thing I did was run the firmware updater that seagate provides. Its on their downloads page..

It didn't recognize my drive as needing a firmware update. So I got ****** and did what any mac owner would do... Call home.. Apple found the same solution I was seeing in some places. DELETE the seagate backup plus extention. System/Library/Extensions/SeagateBackUpPlus.kext

Restart your mac. See if that helps your eject or restart issues. My guess is it didnt. The next thing I did was run the firmware update again. Plug your  hard drive in again. It might take a second to recognize, but the firware updater (1.2.2 I think) will see theres a firmware upgrade needed. I think the extension kept it from seeing that.

Update as quick as you can before the drive ejects... The updater will prompt you to unplug and plug it back in. It should say update successful. The drive will dissapear again, but this time on a safe eject. Reboot the comp, or unplug and plug the drive back in. The drive has been up and running, falling in line with my other drives and rebooting when I want it to.

Hope that helps....If you need more help, my email is on my website www.humbledown.com

I also tried Jettison and it did not help. My external hard drive is still being randomly ejected. Not only is this annoying, but I now can't rely on Time Machine to make regular backups since the hard drive is not connected most of the time. This is really disappointing. I just hope the upgrade to Mavericks fixes this. Otherwise I will have to do an erase and install, and just hope I don't lose any important data in between.

All,

There is the intent to provide a supplemental release to 10.8.5 which, in part, is stating that it will fix the "improper ejection" when the Mac is put to sleep.

" Fixes an issue that may cause external hard drives to be ejected after the computer goes to sleep"

http://www.macrumors.com/2013/09/24/os-x-10-8-5-supplemental-update-being-prepar ed-to-address-facetime-camera-and-other-issues/

Lets keep our fingers crossed....sounds hopeful......................

Hi,

This is good news. Fingers crossed.

No kidding... this is great news!

Really.......a long time coming!  I tried everything under the sun to correct this problem to include a clean install of ML but all to no avail.

I'm currently on OS X 10.8.5 (12F37) on a newer iMac. I have been having unexpected umounts for at least the last OS update (maybe the one before that, too). With the most recent update, this unmounting of external drives became much worse, to the point that CCC and TimeMachine no longer worked.

I tried all the suggestions above, to no effect. Then I turned off Screen Saver - et voila! No more unexpected unmounts.

This may not work for others, but for me, turning off screen saver solved the issue. I still need to try turning on the Display Sleep again in the Energy Saver CP. I really don't want to turn my monitors off every time I leave the computer.

Ted

I'd edit the original reply if I could :- (

Seems whenever a display change is made, screen saver _or_ display sleep, external disks are put to sleep.

Guess we wait for an Apple fix.