Q: External Hard Drive spontaneously ejecting after upgrade to Snow Leopard

I have the WD drive directly plugged to my iMac on an USB port. It evens disconnects during Time Machine backup if the iMac is awake... =/

05/06/11 00:02:11          com.apple.backupd[307]          Copied 62.8 GB of 607.1 GB, 149623 of 618213 items

05/06/11 01:02:12          com.apple.backupd[307]          Copied 117.1 GB of 607.1 GB, 149825 of 618213 items

05/06/11 02:02:13          com.apple.backupd[307]          Copied 164.9 GB of 607.1 GB, 149990 of 618213 items

05/06/11 02:25:38          com.apple.backupd[307]          Stopping backup.

05/06/11 02:25:38          com.apple.backupd[307]          Error writing to backup log.  NSFileHandleOperationException:*** -[NSConcreteFileHandle writeData:]: Input/output error

05/06/11 02:25:38          com.apple.backupd[307]          Error: (-36) SrcErr:NO Copying /Users/manu/Movies/tvshows/Heroes 3/Heroes.S03E14.HDTV.XviD-LOL.avi to /Volumes/WD/Backups.backupdb/iMac de Manuel Bravo Veiguela/2011-06-04-230211.inProgress/3E4C907F-DD27-4E74-87FB-3B7C7F7233C6/Maci ntosh HD/Users/manu/Movies/tvshows/Heroes 3

05/06/11 02:25:39          com.apple.backupd[307]          Stopping backupd because the backup volume was ejected!

05/06/11 02:25:40          com.apple.backupd[307]          Error writing to backup log.  NSFileHandleOperationException:*** -[NSConcreteFileHandle writeData:]: Input/output error

05/06/11 02:25:40          com.apple.backupd[307]          Error writing to backup log.  NSFileHandleOperationException:*** -[NSConcreteFileHandle writeData:]: Input/output error

05/06/11 02:25:40          com.apple.backupd[307]          Error writing to backup log.  NSFileHandleOperationException:*** -[NSConcreteFileHandle writeData:]: Input/output error

05/06/11 02:25:40          com.apple.backupd[307]          Copied 150090 files (182.0 GB) from volume Macintosh HD.

05/06/11 02:25:40          com.apple.backupd[307]          Error writing to backup log.  NSFileHandleOperationException:*** -[NSConcreteFileHandle writeData:]: Input/output error

05/06/11 02:25:40          com.apple.backupd[307]          Copy stage failed with error:11

05/06/11 02:25:40          com.apple.backupd[307]          Error writing to backup log.  NSFileHandleOperationException:*** -[NSConcreteFileHandle writeData:]: Input/output error

05/06/11 02:25:40          com.apple.backupd[307]          Error writing to backup log.  NSFileHandleOperationException:*** -[NSConcreteFileHandle writeData:]: Input/output error

05/06/11 02:25:40          com.apple.backupd[307]          Error writing to backup log.  NSFileHandleOperationException:*** -[NSConcreteFileHandle writeData:]: Input/output error

05/06/11 02:25:41          com.apple.backupd[307]          Backup failed with error: 27

05/06/11 03:02:30          com.apple.backupd-auto[875]          Not starting scheduled Time Machine backup - time machine destination not resolvable.

This issue is still present in 10.6.8 after applying the Combo update. Can any Lion beta testers confirm whether it appears to be fixed in 10.7?

Same problem here with two separate external drives. Had it with Snow Leopard and now also with Lion.

It's getting very frustrating as I've been considering buying yet another external drive for backup pursposes but I'm hesitant to do so as I've got not confidence that I won't have the same problem with a new drive..

Having the spontaneous eject issue as well. It seems to happen when the machine is accessing one of the drives for one reason or another, the issue is intermittent (hard to predictably reproduce). My drives are connected to an  IOGEAR powered 5 port USB hub/card. My drives are:

- 2, 2.5 inch HDS Travelstar 500GB 7200 pm drives in ULTRA cases (USB 2.0 interface connection)

- 1 WD 250GB drive, 5400rpm

System:

- 11" MacBook Air, 4GB RAM, 1.6 Dual Core, 128GB Drive

Recognizable pattern:

- spontaneous eject happens when an app of one sort or another needs to 'read' or look at those drives. Sometimes I can do the smallest thing in an app, and for some reason a disk will eject.

- will get message about disk not being ejected properly

It is not the same disk everytime either. It can be any of the three.

Update to my last post above: I am running Lion (Had the problem with Leopord as well), and it does seem that Time Machine can be a trigger, but it may not be the only one. It can happen when I request TM backup now (manually, outside the normal sched), and/or when I turn TM on or off in prefs. I've seen it happen at other times as well.

Sorry for the multiple posts: Also noticed that it will spontaneously disconnect a drive or three when connecting or disconnecting from a Parallels VM I have stored on an external drive.

One other note about my config: the drives in question are NTFS format, and I have MacFUSE with NTFS For Mac OS X Installed to read and write to these drives. I also have a FAT 32 formatted drive connect, but something tells me with the number of posts and views on this forum, that the issue is not specific to drive format.

Came to this forum looking for a solution, and see there isn't one yet.

I have the same issues - Lacie USB drive disconnects randomly. It sometimes happens while I'm copying files to it - but it doesn't happen every time and I can't always repeat it. I shut the drive off, then on, and it remounts.. but then the file I was copying is 'ghosted' and I can't imagine this is good for file structure.

Anyway, will keep peeking on here to see if there's a solution. I'm on 10.6.7.

I guess you can add me to the growing list of people with Hard Drive problems and Apple!

I just bought a new iMac i5 3.1Ghz, with Snowleopod 10.6.8 installed on it, and attached a Western Digital 2TB HD to it to begin backing up my two 1TB Buffalo HD's. It was planned to take around 3 hours and so I left it to run... came back an hour latter to see the 2TB HD was irritatingly ejected!

After trying everything suggested by this and other forums, still no success. It picks up the drive to begin with and then just as quickly tells me I ejected it improperly! B#%L S%@T

If I wanted these types of issues I would have stayed with my Windows 7!

Not sure if I'm going to get any help, it seems the same problem and nobodies solving it, except for random acts of try this... Not really something I wish to trust in handling all of my digital files.

My question to this forum is, where are the Apple Technicians and what's being done about this, as it looks to be an issue dating back to 2009!!

uhm. i dont have any of these problems.. i blame layer 0.

When will this issue be addressd? i  have the same problem.. i have to use other laptop to copy files from 1  drive to another..

Just to add here: I have four external drives. One Seagate Freeagent, one Seagate Expansion drive, and two WD "mybook" drives. Three of them behave perfectly fine, but the Seagate Expansion drive ejects when my iMac goes to sleep so that when it wakes up I get the "you did not eject your disk properly" error. It's very odd when three drives work fine but one insists on being a problem. That tells me it's not Mac OS but something about this drive, or something about Mac OS with this particular drive. The problem drive is also my Time Machine drive, but I don't think that really has anything to do with it. I don't know, but it's very annoying. I'm probably going to try this fix ....

Adding my "me too"; maybe this straw will push the camel's back beyond the tipping point. Or not.

On 10.6.8. I have repaired a few times--it seems to work, but then so do random unplug and hot plug or power cycles. I thought the HDD was getting too hot, but it can fail when cold. I just hope TM is not going to be corrupt when I need it.

Same issue - using an iomega FW 800 and a WD FW 400 daisy chained off of it

both drives stay up most of the time, but i will notice that the drives are unavailable.

once i shut both off and turn back on they are fine, but still.

I'm facing this problem with a Western Digital My Passport Essential SE 1 TB. The problem started immediately on upgrade to OSX Lion. It's disheartening to see several open threads on this topic on apple support and the company not doing anything about it. The phone support guy simply dismissed me off saying he never heard of the issue and I should contact the manufacturer of the drive. Apple employees are trained very well to lie blatantly!