Disk not ejected properly

Thanks. That's the most cogent and understandable response I've seen, even though I don't like the answer. It's not entirely clear why this didn't use to happen in much earlier OSes, at least not to me. Maybe it did happen, and the OS simply didn't produce the DNEP message. I think I can recall times when the external drive had been disconnected when I tried to access it, and I had to start it up again. Anyway, it doesn't seem like most people are losing data as a result.

I Would tend to agree with both of you. I can't remember having this problem in the past with regards to my Mac going to sleep. Mind you for the last couple of years I haven't been allowing my Mac to sleep" I can't remember why I made this decission, but it may be linked to the "not ejected properly" issue. As far as I understand three of my hard drives have individual power supplies, therefore the USB connection would only transfer data. So if your Mac goes to sleep the hard drives still have their own power, allowing them to sleep.

I've exhausted my efforts to find a solution to this problem, so for me it's "never sleep" or sleep and hope my drives don't get damaged.

I don't know what WMS44 has done, but I /did/ remove all power (internal battery connection) from my Macbook Pro Retina (mid-2012) for about half an hour in the process of replacing my SSD, and the problem with DNEP was unchanged. I know you have said repeatedly to remove power for 2 hours, but it's hard to believe that without any power the capacitance would hold that long. I suppose anything possible.

I've also tried all the other remedies suggested here, including cable changes, removing the configuration folder from the library, etc., etc. But my DNEP issue so far occurs /only/ with my USB 3.0 WD MyBook drive, not my other USB or Thunderbolt drives.

I suspect this DNEP issue is multifactorial cross various OSes and computers and HD, and that there is not a single explanation or fix that "fits all." What baffles me is that Apple, which surely must be aware of this issue from support calls to Applecare for those who have Applecare, hasn't tried to figure out what is going on by looking at Console logs, error reports, and the like.

Sorry , I should have mentioned that I did disconnect everything from my Mac Pro and powered down for 10 hrs. Didn't work for me.

I Also gave RObster50's solution a go. Still no luck.

I Reached the conclusion that it was down to the inateck PCI expansion card.

I'm sure if I swapped one of the hard drives to one of the original USB 2.0 ports it would be fine. But that still doesn't solve my USB 3.0 to HD's issue.

There are variations of issues withing this chat. Faulty or poorer quality USB cables will cause your HD to flag the "not ejected properly" warning. Last year my Maxtor would do this whilst I was working on my Mac, until I changed the cable. That solved that particular issue.

Robster50's solution will also work for some, makes sense.

LaraCroft_NYC's solution doesn't really make logical sense, but there has been evidence of peripherals causing issues. When disconnected and allowing your Mac to completely power down followed by reconnecting peripherals results in some magical results.

I now know neither of the above is linked to my issue.

Another reason I have decided not to use sleep is because SSD's don't really need to be put to sleep (so I read somewhere). I have three internal SSD's including my OS drive.

The only reason I originally wanted to use sleep was due to the fan noise coming from my Mac and Hornetteck enclosure. It's not loud but it would have been nice to shut out the sound all together.

I have now decided that I can live with the distant hum compared to banging my head against a brick wall trying to find a solution that would result in making other sacrifices.

"I have now decided that I can live with the distant hum compared to banging my head against a brick wall trying to find a solution that would result in making other sacrifices."

Banging your head against a brick wall makes noise, too. My wife tells me that my swearing at my computer doesn't seem to help the situation, either, but it makes me feel better.

I think we've come to a dead end here, but I like the idea of not putting a computer with a SSD to sleep--I think I'm going to try that method and see what happens. I don't have it set to sleep automatically--only the screen--and it seems that I sometimes get the DNEP message after the computer has been idle for a while, and not having gone to sleep, but I'm not sure.

Ha! Ha! KenV54, It hurst more as well.

OK - one update for you that has solved my issue.

I thought I could afford to waste £2.99 on Jettison (app store) and guess what. Ejects my external HD's on sleep and re-mounts them on wake without any issues. Just a little confused that a new USB HD has appeared on my desktop called EFI. It's formatted as MS-DOS(FAT32), so I'm guessing this has something to do with WMware fusion (parallels). Just really confusing that it appears as a USB volume.

I just though I'd post some info about Jettison, which seems a little strange. Purchasing Jettison from App store give you version 1.2, however there is an update to 1.4, which give a few more settings. The following link describes how to get the update if you have purchased on the App store.

http://justaguythinkingblog.blogspot.co.uk/2013/12/a-solution-to-problem-with-ma c-osx-109.html

Reverted back to Jettison 1.2.4 because the update as described from the link on previous post didn't work for me.

I'll probably contact the vendor to see why.

UPDATE - Rather than adding more and more posts on here - Jettison 1.2.4 has stopped working. STRANGE!!!

There seems to be a difference between allowing my mac to sleep through Energy Saver and forcing to sleep using the Jettison interface.

Whether I use Jettison 1.2.4 or Jettison 1.4.2, allowing to sleep naturally is fine. But using Jettison to sleep doesn't work with either version.

I also get a black screen on wake for 5 seconds, which was worrying, but then all drives have mounted with no evidence of "not ejected properly" warning.

This is going to be my last post for a while, as I have all ready flooded this chat...

UPDATE

Leaving my mac to sleep whilst running "Jettison" worked fine, however leaving it in sleep for a length of time threw up the "not ejected properly" warning.

I got in touch with the developer of "Jettison". What he had to say makes so much sense and may apply to others suffering from this irritating issue:

"Open your Energy Saver settings in System Preferences and turn off "Wake for network access". What's happening is that there are scheduled tasks that wake up your machine while it's sleeping - the trouble is that it only wakes partially, and in the process can get itself confused if disks aren't there that it expects to be there (basically, all external disks)."

I'm not 100% sure how network access during sleep provides as an advantage apart from checking for updates etc, or perhaps accesing your mac remotely.

All I can say - is that my system is now behaving as it should. Sleeps and wakes without the "not ejected properly" warning.

The "Jettison" developer went on to comment:

"This seems to be a pretty glaring bug in OS X"

wms44, thanks for that advice. I just turned off "Wake for network access" in Energy Settings and will see if that does any good. I downloaded Jettison and am trying it for 15 days to see if it works. At first, it did eject my disks, but then I started getting the DNEP message again. Will see if that setting helps.

I've now tried all the options that don't involve Jettison. (I did use Jettison once a while back, but not worth the trouble.) Checking or unchecking all combinations and permutations of the boxes in Energy Saver preferences, putting the MacBook to sleep, not putting it to sleep, not letting it go to sleep with inactivity, etc. , results on no change in the DNEP notifications. I even get them while I'm working at the computer. I've removed the power supply internally in the MacBook, let it sit, but no results.

As they say in New York, fuggedaboutit, there is no logical workaround. It's up to Apple engineering to look at it and see exactly what is happening to trigger the disk disconnect. Surely, if we can send a man to the moon, or Apple can build an iPhone 6 that's almost as good as my new Blackberry Passport phablet (check it out, folks, before dismissing the idea), the computer scientists at Apple could come up with an answer to the DNEP problem. They just don't want to bother with it.

Curious why people don't like Jettison? I just installed it a few days ago (version 1.4.2) and it has worked flawlessly. It ejects my external HDDs before my iMac sleeps, and remounts them when it wakes up. I have a nightly backup scheduled where Energy Saver wakes the computer and SuperDuper runs automatically to make a bootable clone, and that has worked perfectly. Before, without Jettison installed, I would frequently awake to find "disk not ejected properly" errors.

Yes, Apple should fix this, but in the meantime Jettison is working well for me.

I've tried a couple different USB 3.0 cables, with and without running it through a powered Amazon Basic USB 3.0 hub.

I just found another USB 3.0 cable from Other World Computing, which, by the way, I recommend highly for all third party Mac stuff, like internal SSD upgrades. I'll post here after a couple of days and let you know.

Much as I would like to blame Apple for this altogether, I still don't know if maybe the WD MyBook drive is somehow at fault.