"Disk Not Ejected Properly" error after El Capitan

Bizarrely I discovered that if I linked my HD via a hub (I mean the HD which was originally causing the problem) it worked perfectly, but connecting it directly it was (not ejected properly every time, immediately. I have updated this morning to 10.11.2, and it's still the same. Disk not ejected properly if I connect it direct, but fine if I connect through the hub. I have just connected the old one directly, and the same as before, it is working fine. I don't understand how a small old hard drive is doing fine, but a new bigger one is causing problems. But the update certainly hasn't changed anything for me

I take back my last comment! Now the old HD has "not ejected properly" So the update has made matters worse for me. ! will try that in the hub now.

Have done everything in this thread, and still no joy. System updates, switching ports (hub has it's own power), zapping PRAM etc etc... Issue still occurs after sleep process. Got so used to it now, i'm almost past it. One thing that is consistent, only became apparent when updating to El Cap. Fed up of submitting feedback, as this issue is still not being fixed over the various betas of El Cap. I read somewhere that it could be related to Time Machine, but who knows.

I am with you. Tried everything - no help. I am frustrated because this is the disk I use for Time Machine and it won't even mount on my desktop unless I have everything powered down, I turn on the drive first, then boot the mac. Then I run Time Machine manually - on demand. Not a great solution.

Sure would be nice to get this fixed. I hate to spend money on another drive hoping it will work, only to find out it has the same issue.

Another issue I have, not sure if it's linked to this but after restarting, El Cap just hangs on startup unless i unplug the USB hub with all its' peripherals. I switch off then on again, it boots and once on desktop, i plug the USB hub back in and the volumes mount. There is something definitely broken within the USB connectivity for external drives on El Capitan.

That's interesting.... because I have two WD Passport drives; one of them is ejected, but the other, which is for Time Machine backups, doesn't. My machine is set to only turn the display off, but not go to sleep, so I assume it's backing itself up around the clock. I'm so frustrated, because my Windows machines have always been the ones that make me furious, but now it's the Macs. I've also had problems trying to copy PDFs to my iPad through either iTunes or iBooks, and my iPhone can't decide whether it wants to use the music I synched to it, or my iTunes Match library. <sigh>

Is there another update due, or do you mean 10.11.2. Because mine has been worse since updating to 10.11.2. It completely ****red one of my HDs, so I had to erase and reformat it, and now it won;t accept it at all. That was the one which it WAS accepting before the update to 10.11.2.

Yep, same here. Made it through the first night okay, but disk was ejected the following morning. I'm going to try the hub, to see if that helps, but otherwise, I may use my PC for everything else. I'm so disappointed; the "it just works" thing isn't true anymore.

I have a Lacie quadra d2 that will not mount on my imac with el captain 10.11.2. I changed the power supply, it does not show on disk utilities, it gives me:

Unknown Device:

Maximum Speed: Up to 800 Mb/sec

Connection Speed: Unknown

on my firewire screen.

years of work on here!

HELP!!!!!!!!

BROFATHER

Another "me too." I backed up my Yosemite HD to an external USB3.0-attached drive. No problems. After a fresh install of El Capitan, the drive won't stay mounted for more than about 3 minutes. I can't even restore anything from it because it won't stay attached long enough. I can't believe this isn't fixed yet.