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B Gallagher · 07:26 PM

Hello all,

I've got two external HDDs - one is a Seagate 750GB SATA drive inside one of these:

Over the past few weeks I've been noticing it playing up a lot. The fan's going quite fast, so normally I unmount the drive before I sleep. However, quite often I have gone to click on unmount within Disk Utility, and it says that the drive cannot be mounted, even though if I don't have any files open on it.

More recently, it hasn't been deleting files properly. if I click on a folder on the drive and go Apple+Delete, I get the 'delete' chime, but the folder doesn't move to the trash. And now, for some files on that drive which I have managed to move to the trash, I am getting the following error message when I try to empty the trash:

Despite all this, verify and repair both tell me that the drive appears to be okay. Understandably, I'm somewhat sceptical.

Edit: When I try to rename files on the drive, I'm getting the following message at the moment:

(In this example, the file's original name was "301".

I've already backed up most of what's on this drive to my PB, MBP, and my Time Machine drive. I'm planning to move what's left on the drive over to another external, zero out everything, and reformat this drive. I'm just wondering though, can anyone who knows a bit more tell me if this will actually fix the problem? Or am I likely to get these same errors again once I erase and format the drive? Any can anyone recommend anything else to try?

Thanks in advance.

seanc · Dec 2, 2008, 06:46 PM

Seagates are quite reliable drives, it could be the chipset in the enclosure. Is it firewire or USB?

B Gallagher · Dec 2, 2008, 07:05 PM

The enclosure is both Firewire and USB, but I only connect the drive itself via FW. From the specs, it says that the chipset is an Oxford 924 DSA.

B Gallagher · Dec 4, 2008, 12:06 AM

Update: If I try to reformat the drive, I get the following error message:

Disk Utility is also showing the disc as having much more storage than it actually does!

reader50 · Dec 5, 2008, 11:04 PM

If you have a PowerMac or MacPro handy, I'd take the enclosure apart, and stick the drive in an internal bay. At least that way we could see the SMART status. Or move it to a different enclosure for further testing.

Disk Utility could be right if the drive were originally a 1TB drive that Seagate formatted & sold as a 750 because of a few bad heads. If that were the case, the drive might format at an odd size in between 750 and 1000.

New drives are very cheap today, and enclosures aren't bad. If it's in warranty, RMA it. If not, and you want to invest the time, swap parts around a bit and test further. But your data is harder to replace, and you can get TB drives on sale for under US$100.

Try booting from the OSX Install disk, then do the format from there. That would eliminate your OS install as a suspect. Try connecting via USB to attempt the format, to eliminate questions about the FW interface/drivers. Or just get a new drive, and pitch the one you've found unreliable.

B Gallagher · Dec 7, 2008, 07:18 PM

I don't have PowerMac or MacPro available to test out the SMART status unfortunately. And my other enclosure is IDE - this one is SATA.

I don't think Disk Utility was right regarding the 810.9GB size - this disc was bought new off Seagate, and it's branded as a 750GB model.

I reformatted the partition the other day. Things were working fine for about a day, then the similar error messages returned. I think I'll just backup all my data, erase the drive, and RMA.

Thank you for your help!! ^^