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TICKET ARCHIVE -> can't read external hd!

ramji241 - Apr 18, 2006 - 7:54 pm

Hi, I want to move the iPhoto library from my laptop hard drive to an external hard drive. I have a partitioned 128MB external HD, and ran the Disk Utility program with the partition where I wanted to store my pictures. That program gave me an error when I tried to format my partition as Mac OS Extended (Journaled) and now I get a Disk Insertion Error when I plug my external HD back in. My Mac can't see any of my partitions! Please help...

ScottW - Apr 18, 2006 - 8:18 pm

What type of device is this? At 128MB, it is probably a USB Thumb Drive? Please provide specifics.

Thanks.

ramji241 - Apr 18, 2006 - 8:44 pm

I apologize - that should be 160GB. It's a Western Digital external hard drive that has the problem.

ramji241 - Apr 18, 2006 - 9:29 pm

Hi Scott, I've copied below the log from the Disk Utility manager so you can see what I tried to do and the error I received. Hope this helps. By the way, I wonder if the problem is related to installing Mac OS9 drivers during the re-format. I didn't know to do this, so I didn't. If you think this may be the problem, can you suggest a way to fix it? Thank you.

**********
Apr 18 17:20:04: Disk Utility started.

Preparing to erase : “PICTURES”
Volume Erase failed with the error:

Could not unmount disk
Erase complete.

Error with volume erase Could not unmount disk
Erase complete.

Preparing to erase : “PICTURES”
Error with volume erase Could not write partition map
Erase complete.

ericl - Apr 21, 2006 - 10:24 am

The error "could not unmount" says your Mac thinks the disk is in-use by something.

You say you have a 160 GB Western Digital disk, and you have a "partitioned 128MB external HD", so you need to supply a little background info on the external disk - it appears that this disk may have been used for other things before what you are doing now. So, just what do you mean by a 128 MB partition?

If this was used on MS Windows, this writes a label on the disk & nothing else can use ANY of the disk.

Thanks, Eric

ramji241 - Apr 21, 2006 - 10:46 am

Hi Scott,

Please disregard the 128MB - that was a typo on my part. It's a 160GB external HD with 5 partitions on it. All partitions were originally formatted as FAT32 so they could be used on both Windows and Mac. I just wanted to reformat one partition as Mac OS Extended (Journaled) so that I could store my iPhoto library there, but when I tried to do so with Mac's disk utility it gave me the errors I've copied above. Last night I was able to download a program to recover most of the files from the hard drive, so I'm not so concerned about the data on my other partitions. But I'd still like to know why the Mac program failed me.

ericl - Apr 21, 2006 - 10:59 am

It failed because Windows writes a label on the disk. This label prevents you from plugging this disk into any other non-Windows computer.
If you want to share this disk as you specify. it will have to be plugged-into a Windows computer & shared over Ethernet.

Thanks, Eric

ramji241 - Apr 21, 2006 - 11:06 am

Thanks Eric, but I'm a bit confused. I had been using the drive before it failed on both a PC and a Mac. My wife had loaded Quicken for Mac on her Mac and had saved the Quicken file to the external hd. I was also able to access files stored on the hard drive on both computers. So what do you mean by "share"? Is it just that the Mac can't reformat a partition that had been originally formatted in Windows? If so, is there a way that I can do this successfully?

ericl - Apr 21, 2006 - 11:43 am

So, did you originally partition this disk on a PC or a Mac?

The Mac has an option to partition in a format that both PC & Mac can use

ramji241 - Apr 21, 2006 - 11:47 am

I originally partitioned it on a PC as FAT32. I thought that was a format the Mac could read as well.

ericl - Apr 21, 2006 - 12:46 pm

OK, let's do this:

plug the disk into the Mac

What does Disk Utility see?

It should see this device, then under the device it should list all the volumes/filesystems on the device - I think you said there were 5?

Thanks, Eric

ramji241 - Apr 21, 2006 - 1:35 pm

Disk Utility doesn't see any of the volumes, and all the options are grayed out.

ericl - Apr 21, 2006 - 6:35 pm

Does it see the disk?

ramji241 - Apr 23, 2006 - 3:02 am

Yes, it sees the disk, just not the partitions.

ericl - Apr 23, 2006 - 10:40 am

OK, that's good. At this point your Mac recognizes the raw disk, but does not think there are any filesystems on the disk (HFS+, FAT32, etc)

The next thing to look at on the Mac would be more in depth info on what your Mac THINKS is on this disk:

Go to the blue apple icon; select "about this Mac"

Select "more info"

Under "hardware", select the "bus type" your disk is attached to your Mac with (ATA, Firewire, USB)

Send me the output

The next thing would be to plug this disk into a Win host & see what tis host "sees" on the disk.

My guess is that Win will see the disk & some Win partitions/filesystems on it.

If this is true, then it has been my experience that Win has put a "label" on the disk preventing any other O/S from accessing that disk

Thanks, Eric

ramji241 - Apr 24, 2006 - 1:02 am

Hi Eric, I've pasted the output below. My Windows computer couldn't see the partitions either. Only after I downloaded a data recovery program could I see the old partitions and the files in them, but on its own Windows couldn't detect the partitions at all.

External HDD:

Capacity: 149.05 GB
Removable Media: Yes
Detachable Drive: Yes
BSD Name: disk1
Version: 6.02
Bus Power (mA): 500
Speed: Up to 480 Mb/sec
Manufacturer: Western Digital
OS9 Drivers: No
Product ID: 0x0404
Serial Number: 57442D5743414C3937313630323739
S.M.A.R.T. status: Not Supported
Vendor ID: 0x1058

ericl - Apr 24, 2006 - 9:50 am

It looks like something has corrupted the filesystems on this disk; at least some of the data is still there, but neither O/S can read it via their "filesystem interface".

It is most likely that the disk hardware is good.

Is it possible that you disconnected the disk while one of it's filesystems was in use? - this can corrupt your filesystem.

You can attempt to recover data, then reformat/repartition your disk.

Thanks, Eric

ramji241 - Apr 25, 2006 - 1:01 am

I'm positive that the drive wasn't disconnected. Nevertheless, I did manage to use a Windows program to recover my data, so now I guess I'll reformat my drive. But I'm hesitant to use the Mac Disk Utility program since it caused me this problem in the first place. It seems it must be faulty. Can you suggest a good program to use to format the drive so that I can have multiple partitions as FAT32 and one partition as Mac OS Extended (Journaled) for my iPhoto library? I appreciate all your help, Eric.

ericl - Apr 25, 2006 - 9:13 am

I don't think "Disk Utility" is faulty. I just read the help section & it says that the "partition" operation erases all the file on your disk.

From reading the help, it looks like you should do this:

(1) Partition with disk utility on Mac - use the "options" button to create MS-DOS partitions & one Mac partition

(2) Test on both computers

Thanks, Eric