HELP: WD External Hard drive disconnecting by itself after Maverick OSX update.

Same issue for me using a WD Elements via USB, both on a Mac mini 2011 and MacBook late 2008 model.

Seems like I can narrow down the problem to the situation when I write to a sparseImage file. Writing the same data directly to the disk works fine. Using an image will make the disk eject.

Tested different cables, same result.

Any ideas?

Forget about the image thing. Same problem on a plain file copy action.

I do agree on this theory:

https://discussions.apple.com/thread/5611308?answerId=24050472022#24050472022

Would be interesting to know what hard drive models resp. enclosures people with this problem are using. Maybe they all have a certain controller chip in common? Of course not anyone wants to take a look into the enclosure, but one for each model should be sufficient.

Starting a new discussion here, feel free to contribute with your failing drive:

https://discussions.apple.com/thread/5943136

Thanks!

I am sure it must be Mavericks - happening with a Seagate 1Tb internal in caddy that used to be internal drive on macbook pro until MAVERICKS INSTALL corrupted my drive - had to 1 - spend 5 hours at APPLE genius bar, would not recover/repair drive or install from their cloud system. 2 - install older replaced drive with working snow leopard on. 3 - buy new 1 tb drive to install mavericks on afresh (£78 no thanks to Apple) - 4 - migrate files from snow leopard drive to new drive. 5 - buy data recovery software (wondershare keeps file names, another £80, thanks again APPLE). 6 - recover data from replaced now corrupted hard drive to spare 1 tb external hard drive (27 hours work, thanks Apple). 7 - erase corrupted hard drive and reformat - (still would not repay)r and then 8 - back up via TIME MACHINE - 3 TIMES SAME FAILURE DUE TO PREMATURE DISCONNECTION EVEN THOUGH POWER CABLE WAS KEPT CONNECTED.

next 9 - erase partition; remove partition (computer hangs on preparing to remove) have to switch computer off from power switch as it states if you close disk utility could render disk unusable. 10 - reboot and connect drive - shows in disk manager only unmounted. 11 - create single partition and format in Mac (journaled) drive then mounts. start TIME MACHINE and wait about 8 HOURS FOR IT TO DO EXACTLY THE SAME AGAIN.

GET YOUR ACT TOGETHER APPLE YOU HAVE COST ME ENOUGH IN WORK TIME AND MONEY.

also - every time i have to zero drive as TIME MACHINE DOESN'T DO INCREMENTAL BACKUP OF EXISTING FILES. it starts afresh every time. so memory taken up by previous interrupted backup have to be zeroed (9hr process) before new formatting and restarting time machine. beginning to think it's an impossible task - FOURTH ATTEMPT NOW. (night and day since Monday)

The disks mounting or not and the disconnecting during backup i am convinced are two different issues.

i am convinced mavericks is the problem for disconnecting during back up

1 - i have a seagate 1TB for mac which was corrupted on updating to MAVERICKS from snow leopard (thanks Apple, nice job) 5 hours at genius bar, no change.

2 - meant buying NEW mac formatted hard drive to install on, (£78 thanx for nothing Apple) new mavericks installed fine.

3 - had to erase (security write zeros) corrupted HD, hours and hours

4 - tried numerous TIME MACHINE backups on reformatted drive in Mac OS (journaled) format. 4 attempts, fail, erase, reformat = 4 days & nights (thx Apple)

5 - attempted CCCloner backup - as before back-up got 1/3rd way through then DISCONNECTED DRIVE - ALL THIS TIME I HAD MACBOOK PRO CONNECTED TO POWER SOURCE, so power-saving feature should NOT be consideration. that is of course unless MAVERICKS IS CRAP.

6 - main difference between CCC & TIME MACHINE is with CCC, drive was not ruined and did not need erase/reformat procedure. DOES mount.

any GENIUSES not at the bar?

I'm going to try formatting my Toshiba 1TB exFat drive tonight and copy back in the data! Let's see how that goes! Cheers!

Just had this 'disconnect' problem now with my WD passport 1TB usb3.0 drive. I use it for Time Machine, and it's been working just fine for last week. I have it connected to my Mac mini all the time and it just backup as it will.

Suddenly tonight it got 'disconnected', and I wasn't able to mount it back until I restart the OSX.

My guess is that it turns itself into sleep mode, and in odd ocassions it trigger the OSX to 'think' it is not sleeping, but disconnected 'unsafely'. Since it's not cleanly unmounted, I can't mount it back until rebooting the OSX.

I haven't had a solution yet. However, there is an disk utility by WD that allows you to set the "auto sleep" timer in the WD drive from '30 mins' default to 'never'. I tend not to try it though, as it will keep the disk spinning and gets very hot... another way to kill the drive faster.

Only if you think you really need to drive to be always on, then probably it worth doing so. I'm fine with it disconnecting 'unsafely' once in a while.

I'll wait and see if it happens again any time soon. But just in czase, you can force unmount it by:

"diskutil unmountDisk force /Volumes/DISK_NAME"

As for my case the USB drive is at "/dev/disk3", I could do the following:

"diskutil unmountDisk force /dev/disk3"

To see a list of your drives, do:

"diskutil list"

I suppose if I unmount it, and then connect the WD drive back to USB, OSX should be able to mount it automatically without needing to reboot the system. (But wait to see)

I had the same problem but just found another thread which suggested doing a SMC and PRAM reset

iMac SMC and PRAM reset

After 10 hours all is still connected and have been able to do a time machine backup.

Hope this also helps others

Reformatting drive with Disk Utility solved the problem for me. It's been a week since I did so and haven't had one ejection. This after having an ongoing issue with this pretty much since I bought the WD Passport several years ago. I reformatted using exFat.