Anyone else having problems with external disks unmounting randomly/suddenly on Mavericks?

yes, from your above

WDQuickView

Western Digital My Book 1110 999.5 GB

EFI (disk3s1) <not mounted>: 209.7 MB

Go to WD.com and run their uninstaller program, you have had WD-ware on your Mac, and still have one piece (if not more) remaining on your Mac.

😊

Thanks for t he advice, but I could not find an unistaller on the wd.com site. If there is a link, I'd appreciate it.

Looks like they just removed it alas

http://community.wd.com/t5/News-Announcements/External-Drives-for-Mac-Experienci ng-Data-Loss-with-Maverick-OS/td-p/613777

I have same issue with a canon imageFormula p-208 usb portable scanner. Same disk eject message appears randomly for no apparent reason. I reported to the link posted by Plotiinus. Waiting for software issue to be resolved, as all equipment is otherwise new.

So clearly the issue exists, and just as clearly Apple seems to be doing nothing about it. I wonder what will get them moving. Threaten a class action?

Does anyone have the link to the main thread dealing with this ?

I think most of us are now past the whole - 'its a drive issue' - i've now used 6 different drives and 3 caddy's with 4 other drives with WD, Seagate and Hitachi drives - all disconect at odd times - particulalrly when time machine is on. Its a USB 3 driver issue with Mavericks and it needs sorting.

I think this is the main thread:(

I don't think 10.9.1 Update brings any good. There is nothing in the release note about USB2/3 issues.

Is it possible for the TS to change the subject? It's no longer a question.

Fiddleplay wrote:

Threaten a class action?

Read the terms you agreed to when you accepted the download and installation of Mavericks.

Pete

Found this thread because I'm having the same problem. My set up is a 'brand new' refurbished MBPr 2.3ghz w/ 8gb ram runing 10.9. I have a USB 3 dual hardrive (2x2 TB seagate ) enclosure that just unmounts randomly. Everything is out of the box new so I'm trying to find a solution. Any help would be awesome. Thanks!

We as mentioned I am using WD bare hard drives in a USB3 caddy (ICY BOX) and I have had no problems since using a USB2 cable - so change your cables first and see what results you have

Sorry guys, but USB2 is all that I have been using and I have lost 3 drives. Lost as in they won't reformat.

Having the same issue here. Have a MacBook Pro 2013 and several different drives and USB 3 Memory sticks. All unmount unexpectedly under mavericks. They worked fine under the previous OS. The issue only happens when connected via USB 3 hubs. If I connect direct to the laptop, it's fine.

I loaded the update, but it did not help theporblem. I cannot understand why Apple is dragging their feet with this, and I am extremely concerned that I will lose all that is on my hardrives.

I tried the USB 2 cable solution but still no success.

Just piling on. Same problem: random unmounts of external USB drive with imroperly ejected disk error after installing Marvericks. Never saw the behavoir before the 'upgrade'. Should have stuck with 10.8 as the external drive is one of the main repositories for my home server. Have to frequently cycle the power on the external for the mac mini to see it again. Not easy when you're halfway across the country!