External HD Problem in Snow Leopard

I have exactly the same drive as you. Iomega 2.0 TB. Brand new and never worked. It shows in Disk Utility as an 8.59 gb drive and won't format. Then I get the same POSIX reply

I was having a similar error, but with a RAID5 hooked up with an areca RAID card. The thing that finally worked for me was:

1) selecting 'Partition' rather than erase
2) select '1 Partition'
3) choose "Free Space" and apply
4) once this was done I was able to choose "Mac OS Extended (Journaled)" and partition again and it worked!

Thank you Ed...

I followed the steps you did and it worked for my single external USB drive. I was having the POSIX problem as well. Time machine is working perfectly now.

So you folks do not have to hunt for the previous thread, here's what worked:
1) selecting 'Partition' rather than erase
2) select '1 Partition'
3) choose "Free Space" and apply
4) once this was done I was able to choose "Mac OS Extended (Journaled)" and partition again and it worked!

I hope this helps someone. Thanks again Ed for your solution.

Doesn't work on mine. (still same posix error. It works without any problem used with an XP machine).

OS version: 10.6.2

r.kampy wrote:
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!

worked for me.

Tried it all, nothing works for me.

I also have been having this problem, but the drive was already in my computer (2nd drive using MCE's optical drive replacement) and then it started to "fail". it first started with not being able access the drive for writing or reading but could find files, and iStats menu would show the drive constantly reading at 4kbs. eventually I was getting errors about needing to reinitialize. bought a replacement drive and same trouble after 2 weeks. Even ran spinrite on it on a windows laptop and it came back clean. I have yet to try it but when I get a chance I will try using my tiger disks and see what those do.

I'm not sure if this is the best place to ***** about my external HD problem since it only became an issue after installing the SL 10.6.2 'upgrade', but my Firewire connected LaCie drive is no longer recognised or showing up as connected after working perfectly fine before 10.6.2. I actually had it connected during the 'upgrade' and it was all good but after disconnecting it this morning and attempting to reconnect just now...nada. I'm wondering if there's a setting/pref I need to reset since the alleged upgrade also changed some of my other settings.

Also...WORST. UPGRADE. EVAR.

UPDATE. It's reoccurring, sporadic and unpredictable. Sometimes Disk Utility recognises it, sometimes it doesn't. The only fix I've found is to reboot with the external drive already connected. I'd try it out with all my other peripherals but I'm going back to 10.6.1 before I get a rage on. Running 10.6.2 is like running Vista.

UPDATE:

I tried several of the solutions posted above and nothing worked for my problematic drive.

This external has never worked since I assembled it and tried to initialize it the first time. I always got the posix error or it couldn't unmount or any of the other problems listed above.

It's a quad-interface enclosure from CoolDrives in which I installed a new 1tb Seagate Barracuda drive. I wondered if it was the hardware in the enclosure so I got a different unit from IcyDock, similar to an external raid1 which has been working fine all along.

I swapped the Barracuda to the Icy enclosure and tried it... no dice, same problems. So figuring that it wasn't a problem with the enclosure I grabbed another brand new Identical Seagate Barracuda 1tb 7200.12 drive out of our office stash that we use for backups and installed it in the same CoolDrives enclosure that has been the problem. Plugged it in, it mounted and said that it needed to be initialized, formatted it OSX Extended (Journaled) and set it up as my time machine backup and its been working fine for over 24hrs now.

I have already sent the other drive back to Seagate for a replacement... but as it stands, my problem is solved. I don't know why this would have worked, but it did.

Did you have any luck? i'm having the same problem with the same raid enclosure.

DEWW,

If you were talking to me then, yes. Ever since I installed a new drive in the enclosure everything has been fine. I have been using it as my Time Machine backup for over a week and it has worked flawlessly.

I don't know enough to know why the previous brand new drive didn't work. But I no longer have any issues.

- Woody

Thanks! I switched to Firewire and was able to format my external drive.

Hi - I'm having the same problem as everyone else. I have a brand new Iomega eGo external HD that worked okay with Time Machine for a couple weeks, but now is not being recognized at all.

I have tried just about everything suggested, except for plugging the HD through FireWire (I have an alum MacBook w/o any FireWire ports).

I thought attempting to partition the drive through terminal in the following way would be my best option:


1. Open Terminal
2. Type "diskutil list", that will show you the attached drives. Find the offending drive (mine was /dev/disk2)
3. Then type "pdisk /dev/disk2". Replacing whatever you got in step 2 for "/dev/disk2"
4. Then type "i", and take the default options.
5. Type "w" to write the partition map
6. Type "p" to see the partitions, one should be very large, and labled Apple_free. Mine was #2
7. Type "c" to create a partition. For first block, type 2p (or whatever number you got from step 6). For length, type the number listed under length in step 6, then type a name (If you want to make multiple partitions, enter a smaller number for the length and then repeat this step for each partition, using 3p, 4p, etc as your start)
8. Type "w" to write it, then type "q"
9. You'll get an error, but then you should be able to use Disk Util to fix it.

However, when I try to do step 3, I get a "floating point exception" error message. Is there any way around this?

Are my only options to try & find someone w/Tiger or first format the HD through Windows? Clearly the latest OS X update has not solved this problem...

Hi,

had the same problem here, checked out this forum without solution. One suggested SOLUTION THAT WORKS is to hook up your external harddisk to your mac with a firewire cable (if the harddisk has a firewire port). Erasing, partitioning etc, works fine that way.

Afterwards, you can use the drive through a USB connection of course.

Good luck to all and hopefully Apple will give us a serious solution soon