External HDD unmounts itself!

Hi all,

first of all hello everybody and thanks for colaborate in this forum.

My problem occurs with latest Raspbmc version (24/12/14), but also with previous versions:
I have a fstab entry to mount my external HDD drive at system initialization, but randomly this drive unmounts itself, and graphical interface shows a message like “Unsafe extraction device” (but in spanish); so then I try to navigate into some HDD folder but the shell shows me an I/O error.
mtab indicates that the device is mounted, but if I try to unmount it a “Device is busy” error appears. I found that shell is the process that “owns” the device, so killing the shell and reopening it allows me to unmount the HDD and try to mount it manually, but then automatically it unmounts itself again…
That´s the message system log shows when I boot my raspberry and (touching anything) the HDD unmounts itself:
“ERROR: DBus: Error org.freedesktop.UDisks.Error.Failed - Error mounting: mount exited with exit code 1: helper failed with:
mount: according to mtab, /dev/sda1 is already mounted on /media/WD_500GB
mount failed”

And that´s my fstab content (last device is not usually connected, what fails is the one mounted in /media/WD_500GB):

proc /proc proc defaults 0 0
devpts /dev/pts devpts rw,nosuid,noexec,relatime,gid=5,mode=620 0 0
/dev/mmcblk0p1 /boot vfat defaults,noatime 0 0
/dev/mmcblk0p2 / ext4 defaults,noatime 0 0
UUID=F47A46D67A4694F0 /media/WD_500GB ntfs-3g defaults 0 0
UUID=F4D0C441D0C40BB4 /media/KINGSTON_32 ntfs-3g defaults 0 0

Thanks in advance. I´m looking for a solution in many forums without success.


Start here http://forum.osmc.tv/showthread.php?tid=6123 Specifically check your power supply for volt drop


I think you should check your power supply is up to spec. A low current can cause problems like ‘Device removed’ messages’ appearing sporadically. This happens because the power to the drive dips and is thus disconnected. It sounds like you might be having this issue


Hi ;

Try to check the HDD, I had a similar problem time ago, and remember that solve it with a fschk. and you take care, time after my HDD broke it.

I hope help you

Hi guys

thanks for your quick replies. I will check this and report my feedback.


Hi guys,

as you said, it was a power supply fault. Neither my AC/DC adapter couldn´t supply enough current to my 2,5" HDD, nor my USB HUB.
So I have to buy a recommended power supply.

Thanks and sorry about not check the post @Dilligaf said before.


I have same problem, but i have a self powered external hdd.

To get a better understanding of the problem you are experiencing we need more information, including logs from you. Our wiki contains detailed steps for providing the relevant info we need to help you.