USB disk disconnects randomly

Question

Level 1

35 points

USB disk disconnects randomly

Hello,

I'm experiencing an annoying problem with my external USB disk. At random times (these can be short or long periods), it starts making some noise (like when it's intensively reading or writing) and then it vanishes (like if I had unplugged it). Of course, the system complains with a message like "You have not ejected your disk properly...".
Sometimes it happen 3 minutes after I turn the disk on, sometimes it happen after some hours of use.
And, in the Console, I don't see anything useful (only mds stating "Media not present", but that's obviously after the problem).

An idea what I can do/check?
(P.S: I hope to be in the correct discussion board: the Leopard board had "internal errors" and I could not post there).

MacBook Pro, Mac OS X (10.5.6)

Posted on Apr 6, 2009 3:43 PM

Reply

Answer 1

eww

Level 9

53,028 points

Apr 6, 2009 4:49 PM in response to Anic264b

Your disk is probably intermittently demanding more power than the USB bus can provide to it. You need an alternative source of power for the drive. There are three possibilities:

1. A "Y" cable with two USB connectors on one end to plug into both of your computer's USB ports and deliver power from both of them to the drive on the other end of the cable. This is the most convenient portable solution, but it does require both of your USB ports.

2. An AC adapter for the drive, if it has a DC power-in port on it and you can get specs for the adapter (or the adapter itself) from the drive's manufacturer or vendor.

3. An AC-powered USB hub, connected between the computer and the drive. This has the advantage of giving you additional USB ports.

Reply

Answer 2

Kevenly

Level 1

25 points

Apr 6, 2009 10:15 PM in response to Anic264b

I have had this issue with five different Macbook Pro computers. Three of them 15", two of them 17". Considering my experience with it I doubt it's a hardware problem. I notice in the console log that, preceding the error dialog box that pops up about incorrectly removing the drive, the system tries to journal or spotlight index the drive and is unable to for some reason.

Perhaps the wizards behind the curtains at Apple are aware of this and it will be fixed with the 10.5.7 update.

Reply

Answer 3

Anic264b Author

Level 1

35 points

Apr 18, 2009 2:32 AM in response to eww

Thanks, but this disk has an external power source.
(sorry for the delay for responding, I had troubles searching where I put this question)

Reply

Answer 4

Anic264b Author

Level 1

35 points

Apr 18, 2009 2:41 AM in response to Kevenly

Well, I always see that spotlight and journaling are also trying to operate (as for the failure of this operation, I thought it was simply caused by the disk being unmounted and searched another reason. I think that because I have already tried to disable spotlight and, without spotlight the disk continued to unmount as well).

Even if Apple knows that, I'd love they publish a quick update for that problem and even let us know where the problem is (it's fine to have a problem corrected, but it's so much better to know what was causing it (I'm always curious)).

My problem is becoming worse: last wednesday, I tried to copy a file from my internal HD to this external HD and it unmounted every time (this was a 1.88 Gb file, so it took a long time). I could not move that file at all!
And today, the disk is removed as in a loop (every time it's mounted it gets unmounted in less than 5 seconds). Annoying, annoying, annoying...

Thanks

Reply

Answer 5

JJulian

Level 1

10 points

Apr 18, 2009 3:11 AM in response to Kevenly

I'm having the exact same issue with my MacBook Pro 15" (purchased in February09), *but with firewire drives*. I own six LaCie d2 triple extreme drives, some of them for more than 3 years. These disks have been *extremely reliable and worked with all the computers* I owned and used in the past years.

Since I upgraded to this MacBook Pro, the disks would disconnect randomly, sometimes 1min after plugging it in, sometimes after 3h. I'm especially annoyed as my iTunes music library (220GByte) is stored on one of these drives, and often the *disk would disconnect while playing music*. The error message comes up, the music stops, and I have to restart iTunes.

Extremely annoying. *I've been very disappointed so far with that MacBook Pro*. In 15 years of being an Apple costumer, and heavily using more than a dozen different apple computers (starting with SE/30, LC, IIci, Performa, PowerMac beige G3, G4, iBook, PowerBook, MacBook, iMac G3 to G5, iMac Intel, etc), I never had such a buggy machine before:

- battery takes ages to load, but only holds for 3h
- external drives would disconnect randomly
- FrontRow activeates itself without me asking for it
- Permissions are screwed up, I cannot update certain programs because I "don't own" them
- slow performance even though I upgraded to the 320GB 7200rpm disk, 4GB RAM, 512MB graphics card, fastest cpu

Give us 10.5.7, Apple, I want to use my expensive computer without getting angry.

Reply

Answer 6

Anic264b Author

Level 1

35 points

Apr 18, 2009 5:16 PM in response to JJulian

I agree with you, although most of the annoyances I'm experiencing are related to how Apple made some choices in Mac OS X (e.g pressing the space bar in the Finder now shows QiuckLook (which I never use) while I have taken the habit to make some folders with a name starting with a space (they are shown first in a window ordered by name). Now, I can't reach them with the keyboard because I can't change the fact that QuickLook reacts to it).

Reply

Answer 7

Art.Fry

Level 1

9 points

Apr 26, 2009 9:55 AM in response to Anic264b

I have same problem too. Randomly disconnect. But in my case I already have external USB hub with power supply. And there connected only mouse. I even cant play Quake II normally because my mouse is going to be disconnected.
How to resolve this problem?

Reply

Answer 8

cuellar

Level 1

0 points

Apr 30, 2009 1:31 AM in response to Anic264b

Same problem :((
But in my case it seems it afects only my usb compactflash card reader. The unit is disconnected randomly and this is really annoying.

I've just switching from vista. Ok vista isn't cool but usb ports work properly. This issue is completely unacceptable.

Reply

Answer 9

waptir

Level 1

0 points

May 4, 2009 1:59 PM in response to Anic264b

I have same issue with my macbook, I want to copy a file from my flash drive (8gb atv ocz) it is 2.63 gb sized.
it starts normally then, when getting closer to finish, it allways disconnect my flashdrive and then pop-up a warning message says Device Removal bla bla...
I try 10 more times to copy that file but I cant.
Then I try it on my Asus PC with Windows Vista H.P. it works there is no error about reading or disconnecting.
There is a error with 10.5.6 I think.
Please fix it, I dont want to use PC anymore.

Reply

Answer 10

cderalow

Level 2

290 points

May 11, 2009 9:38 AM in response to JJulian

I'll ditto this issue with a 500GB Western Digital Passport Elite.

Randomly disconnects after anywhere from minutes to days.

Reply

Answer 11

JJulian

Level 1

10 points

May 21, 2009 3:05 AM in response to waptir

Did the update to 10.5.7 improve anything for you? I still have the disconnects, although much less often.

Reply

Answer 12

cuellar

Level 1

0 points

May 23, 2009 11:23 AM in response to Anic264b

My problem was with my USB card reader and now it's solved.

It seems the card reader isn't mac compatible. Works fine with PC.

I got a new one branded (sony) and now everyhing ok.

Reply

Answer 13

Anic264b Author

Level 1

35 points

May 23, 2009 2:26 PM in response to JJulian

Well, I bought another usb disk, to have more space, and, since then, I haven't seen the problem anymore (however, I haven't used one disk alone, always both at the same time). Still, Apple has not announced they corrected the problem in the update log.

Reply

Answer 14

May 28, 2009 6:29 PM in response to Anic264b

I am having the same problem. For months my external drive was absolutely stable. Then, following an update, I began getting the random disconnects, which have gotten progressively more frequent in the last couple weeks. I have updated to 10.5.7 and the problem persists. I have reset the SMC, and the problem persists. I have used different USB ports, and the problem persists. I have tried different USB cables, and yes, you guessed it, the problem persists. And no, my power settings are not configured to put hard discs to sleep.

Apple - FIX THIS. NOW.

Reply

Answer 15

eww

Level 9

53,028 points

May 28, 2009 6:48 PM in response to cjlavesser

I don't suppose you've entertained the possibility that your drive itself is flaky?

Reply