External hard drive ejects on sleep

The problem appears to be across OS Xs. I am still on 10.6.8 on my iMac. I have a a WD 1TB MyBook (Time Machine) connected by USB 2.0 to iMac, and a powered USB 2.0 hub, through which I connect an older 320 MB Iomega used for image storage redundant backup. I've unchecked "put hard disk(s) to sleep when possible." The iMac is set to go to sleep after 20 minutes without activity. A BackUPS is connected by USB directly to iMac.

At unpredictable times, I will return to the computer and find that the two external hard drives are neither on the desktop nor in the finder. Almost everything else seems to work. However, when I try to restart or shutdown from the apple pulldown menu, everything disappears from my desktop (except the desktop picture) and the iMac does not restart or shutdown. The standard drill is that I manually shut down (button on back of iMac) and wait 15 seconds or often much longer, manually turn the iMac on. At this point the external drives reappear. I then run disk utility to repair permissions on the iMac internal HD. Everything works fine for a while.

Sometimes, I will return to the computer and find a "disk improperly ejected" message that will disappear seconds after I see it, or one that stays there until I close it. This can happen first thing in the morning, middle of the night, or sometimes during the day.

Sometimes I will check in the middle of the night and see that the iMac is on. I have never found out why, although it might be TM. On some such occasions, as indicated above, the external HDs have disappeared and the apple pulldown shutdown acts as indicated.

When everything is working there is no sign of trouble. I've used verify disk on the internal HD and it passes.

As far as I can tell, I have one option I haven't tried yet. I've just set the iMac to never go to sleep to see if that helps.

In the meantime, from the 17 pages of comments and the numerous other threads including reports of the same or similar problems, it looks strongly like this is an Apple software problem across hardware and generations of operating systems. I agree with those who say Apple should fix it. One of the frustrating things about Apple is that there is no assurance that it will look at these discussions, do anything, much less let us know that it has done something.

I just made that 18 pages.

Same thing here. Latest MacBook Pro 15" Retina, OSX 10.8.3. USB3 WD Passport drive (going through a powered USB3 hub) is improperly disconnected while asleep overnight, with an error message given on wake up saying it wasn't properly ejected.

Need this fixed!

Paul

Same problem I'm having here with my Late 2012 iMac and an oldish 250GB USB2 powered Lacie portable drive. Continually unmounting when the iMac goes to sleep and not remounting on waking. Was about to take the plunge and purchase a new USB3 drive thinking that might fix the problem but, reading through these issues, I'm not convinced I'll have a much better experience.

I'm still using a FW800 Lacie drive as my TM drive (connected by a TB to FW adapter) and that seems to be fine and remains stable in it's connection. Really frustrating, wish it would get solved soon.

Apparently the solution is to set your Mac to never sleep. I did this several days ago, and since then no lost external drives, etc.

If that is the solution, Apple should rethink the notion of providing what is essentially a broken sleep option. It is absurd that the option might only work reliably when no external devices are attached to the computer.

Apple, are you listening?

Well, its a 'fix' of sorts but environmentally questionable and could limit the life of your Mac. The real and only solution must be for Apple to modify the OS so it 'sees' the external drive on start up. Clearly its been a problem for some time and I find it difficult to understand why Apple have not addressed it. Has anyone found the problem with external drives already configured for Mac use?

I have the same issue: external disk not mounting after sleep. Unproperly disconnected.

Only happens after longer sleep periods. Putting the mac to sleep and waking up after a couple of minutes does lead to this. However, waking up after a night sleep causes the disks to disconnect.

Issue exists across different configurations with an external disk attached to USB 3.0 (MBP Retina 2012) and different disks attached to a Mac Mini 2011 via Thunderbolt -> Lacie eSATA -> Sata Disk. So for me this is no Thunderbolt or USB 3.0 specific problem. I assume it's a system-wide problem.

😟

Disablinig disk sleep did not solve any issue.

My WD MyBook was configured for Mac right out of the box.

Please clarify "Disablinig disk sleep did not solve any issue."

Did you uncheck "put to sleep whenever possible" box or did you set sleep slider to "never" or did you do both?

I suspect you are right on environmental impact and effect on life of computer, but wish Apple were in on the discussion so we could find out if that is what their vast research and experience indicates. I doubt that the manual shut downs and restarts I had to do were all that good for the life expectancy of the hard drive. I don't know whether those clunky on/off switching events were an electrical drain (recall the old debate about whether turning off lights when not in use saved electricity v. leaving them on - a debate that began under the incandescent reign and continued with fluorescents).

For me this issue is not simply about failing to recognize external hard drives, but appeared to involve continued - but broken - recognition of the computer's internal hard drive. Why else, when the externals disappeared did the Apple shutdown and restart commands fail to complete in those circumstances? (They left me with nothing but my desktop picture and a cursor that moved with the mouse, suggesting that some piece of code or permission was broken.)

I unchecked the "put to sleep whenever possible" as I read this might be a possible solution, although, not for me. Disabling system sleep is not a solution for me, as I don't want the system to be running 24/7.

This discussion has been running for 8 months and nothing from Apple. If you know how to get through to it/them, that seems to be where the solution lies...if it/they care. We could all figure out how to report operating system failures; but there seems to be no simple way to find out if Apple is doing anything with those reports. Perhaps someone should go to the press. How about bringing the issue to Pogue's attention?

My main complaint is that USB 3 drives will spin down every few minutes they are not accessed. Even when I uncheck the "put hard drives to sleep when possible" option in energy preferences. It's very annoying to wait for a drive to spin up if I take a 2-3 minute break from editing. It happens all day long!

Woww..can't believe this hasn't been solved!! As a photographer I'm working with an external ssd constantly so this is a big pain in the ***. I didn't pay this much just for the design! Looking forward to getting this fixed.

SOLUTION:

I have a new (late 2012) 27" iMac, and I was experiencing the issue that many of you have reported, with hard drive disconnects each time my machine went to sleep, and the 'improperly ejected' messages as soon as it woke up. My primary external drive is a WD MyBook 3TB unit that I use for Time Machine backups. As a temporarily solution, I changed the settings so that my iMac never went to sleep. While this worked, I never intended it to be the final answer.

I was able to finally resolve the issue by replacing my USB3 hub. I had been using a Lacie USB3 powered hub from a few years ago. After reading a little about these devices, it seems that many of the vendors have followed different standards over the years, so one hub may not actually behave the way another one will (or the way that the actual standard requires).

I purchased the Belkin 4-port USB3 hub that is sold at the Apple store. Since making this change, I have not experienced the problem again. I have literally put my iMac to sleep *many* times just to prove that the problem is really solved. Now, when it goes to sleep, the hub and drives shut down, as expected (all of the lights on the hub shut off). When the iMac returns from sleep, the hub reactivates (all the lights turn back on) a moment before the iMac comes back to life, and the hard drives are visible and ready to use. I have had no further disconnect messages.

I thought I'd let people know about my particular experience. Hopefully, it will help at least a few of you out there...