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External HD Problem in Snow Leopard

I wasn't sure where to post this problem. I'm using SL and I'm trying to format and partition an external hard drive. I get this type of message each time:

Partition failed with the error:

POSIX reports: The operation couldn't be completed. Cannot allocate memory.

After this happens I have to use Windows to initialize the hard drive otherwise my Mac will never see it again. I have tried different formatting/partitioning options but it all ends up the same.

Does anyone know anything about this problem?

Macbook Pro, Mac OS X (10.6)

Posted on Sep 6, 2009 8:33 PM

Reply
272 replies

Nov 11, 2010 10:51 AM in response to lights22

Unbelievable!!! It works!!!!!! After today's snow leopard update.

This is with the case that I've had trouble with for OVER A YEAR now. And it works--after buying multiple different cases & trying 2 extra replacement hdd's of different brands to try to get it working. What a waste. Apple needs to f*cking communicate better--I did send actual bug reports with no response too, btw. Thanks for wasting my money Apple, instead of just saying the issue was on your end. Glad Apple cared. Anyhow, it works for me. It's done. One year later.

p.s. When I plugged in the drive, it first brought up the error 'disk is not readable'. This is from all the of disk utilities failed attempts to get it formatted and erased and constantly failing. I just selected 'initialize', which took me to disk utility where I created a partition (1 partition, GUID), and then erased (no overwriting with 0's), just to be safe.

It's currently cloning with carbon copy cloner with no issues (yet).

*****UPDATE: The disk just ejected itself in the middle of the CCC backup process. 'CCC aborted the task because the target volume disappeared'. I hate apple. I'm trying the backup again. ******

Nov 11, 2010 11:29 AM in response to Apl9

****Update 2: The disk ejected itself again on second CCC backup attempt. I then went to Disk Utility and attempted to just erase free space with zeroing out of data just to be safe, it ejected itself again. So in sum, today's update got rid of the POSIX error for me and allows me to partition and erase (so that's improvement!), but the disk unmounts/ejects itself when in use. Still unusable. Not solved. ****

Nov 24, 2010 11:22 PM in response to Keith Stone

Late reply -
Had same problems as everyone else. This process worked as advertised for me. Thanks for the help.


_____
Original post from r.kampy:

All right,
here is what worked for me:

1) Open Disc Utility
2) Pic any Volume and chose the Restore tab
3) Drag and Drop your Macintosh HD (or any other partition that has the desired format of your target USB HD) into the Source
4) Drag and Drop your USB drive onto the Destination
5) Hit Restore
6) Wait until you see the USB drive in your finder (containing a few files)
7) Cancel the Restore and erase the files that were copied in Finder

It did the trick for me! I hope it will help you guys.

Please let us know if that worked or did not work for you!

Nov 27, 2010 5:08 PM in response to Keith Stone

Same trouble here. Old Iomega 80GB drive with USB connect. Formatted fine on XP. No love with SL. Tried 10.4, terminal, Disk Utility through startup disk, 30GB upper limit, FAT, NTSF everything failed with the exception of r.kampy's suggestion.

Running SL 10.6.5 on an iMac with 2.4GHz Intel Core 2 Duo and 2GB ram.


Original post from r.kampy:

All right,
here is what worked for me:

1) Open Disc Utility
2) Pic any Volume and chose the Restore tab
3) Drag and Drop your Macintosh HD (or any other partition that has the desired format of your target USB HD) into the Source
4) Drag and Drop your USB drive onto the Destination
5) Hit Restore
6) Wait until you see the USB drive in your finder (containing a few files)
(this never happened for me)
7) Cancel the Restore and erase the files that were copied in Finder
(N/A see above)

Note, I got some strange errors at the end of the process and I thought it had failed. Wish I jotted them down but after 9 variants of trying to make this work I was not focusing on the errors...

Hard to believe Windows XP can do something SL cannot!

Perhaps I am a PC?

Nov 30, 2010 2:42 PM in response to Apl9

Apl9, I have the same problem here. Although the suggestions in this thread allows my drive to be formatted and recognized by my Mac Mini running 10.6.5, the drive un-mounts on the second back-up when using TimeMachine. I don't know if this is a TimeMachine issue causing it to unmount or if it's 10.6.4+ related since I went from an old G4 tower to a 2008 mini.

Even aside from my recent troubles, I always found the Western Digital drive problematic in that it would fail to mount at times. And that was with Firewire 400. On the mini, I'm using USB and the mount/un-mount issues persist.

My external Seagate drive (connected via Firewire 400) that I purchased last week seems to be just fine. Of course, I haven't tried it with TimeMachine. But even before that, my LaCie drive was pretty rock solid. It's only been the Western Digital drive that's been screwy.

Dec 1, 2010 7:12 AM in response to thasro

I was having this issue with my external hardrive. Since it was an internal HDD, I had added a "HD password" using my Dell laptop, and when I converted to external, I forgot to first remove the password and got the same Posix error listed here.
Problem was solved once the password was removed from the HDD, and I was able to format it the way I wanted.

Dec 20, 2010 4:43 PM in response to thasro

What a week...

All of a sudden my macbook wouldn't start up anymore, the wheel just kept on spinning. So I started up from Snow Leopard installation disk. Tried verify disk --> "disk is corrupted, repair disk". So I tried. "Disk repair fails, disk can not be unmounted". Tried fsck in terminal, it just kept repairing the same **** error (file size incorrect or something) and then a whole bunch of I/O-errors.

After starting up in tranfer mode and managing to back up most of my data via firewire to another macbook i tried to format my macbook. "Format fails, can not unmount disk". So I force unmounted it in terminal. Now when i try to format it, it just says "POSIX reports: the operation could not be completed. Cannot allocate memory" . Same error when trying eraseDisk in terminal.

Here I am with a totally useless macbook pro... Any ideas?

Message was edited by: ytterzyrkon

Dec 20, 2010 4:55 PM in response to ytterzyrkon

I'd say, yes to useless. It seems that Apple (or maybe Seagate or WD for that matter) has shipped a bunch of bad HDs the past 2-3 years. I say bring it back to them and have it replaced. Hopefully, it's still under warranty. The 500GB HD in my iMac crashed within 6 months. Luckily, it was still under warranty.

This problem has been reported for so long (all over) and no one is raising a hand. Seagate replaced my 1TB Free Agent external without questions within a year of this POSIX problem occurring. Sounds guilty to me.

Message was edited by: GerryML

Message was edited by: GerryML

Jan 8, 2011 10:01 AM in response to Gwendolyn Kelly

Same posix problem as others have reported. My drive: a Seagate Barracuda 7200.11, 1TB, Model 9BX158-303, firmware SD15.

I tried to format with Apple Disk Utility, put it in a Dell Desktop and tried formatting there, bought an OWC enclosure for $70 and tried with FireWire 800 and USB. I was able to get formatting started once under Windows XP but the process didn't complete for over 8 hours.

I finally gave up, tried with the Seagate SeaTools on Windows to run diagnostic tests, they all failed. Checked and the drive is still under warrantly. So spent $20 to get an advance replacement drive from Seagate.

Message was edited by: Paul Derby

External HD Problem in Snow Leopard

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