Recovery options for drives that go missing

It is not that big a deal unless it actually happens to you and then it is a huge deal. It started out as a little note in the Read Me file that came with the Mac OS10.3.7 update.

This note said: 'Unplug all Firewire drives before updating to 10.3.7.' Some people did not read the Read Me and some did but ignored the advice. Unfortunately, of those who updated without unplugging, a small number lost their Firewire hard drives.

The drives would mount occasionally and then mount no more. A month or two earlier, there was a similar situation wherein if you used a Firewire 800 hard drive to boot your Mac, the same thing happened - poof, no more hard drive.

Normally, Firewire hard drives are dependable and an ideal backup medium, but when they disappear so does their desirability as a useful data storage device. However, all is not lost if one of these catastrophes happens to you. Here is the repair sequence that will probably work.

First, disconnect the drive and remove its power supply. After 10 to 15 minutes, reconnect the drive and see if it mounts. If that fails, check with the Firewire drive manufacturer to see if there is a firmware update. If there is, install it and all may be okay.

If the drive mounts and then disappears and then mounts again, interpret that as a sign of trouble. At the next opportunity, transfer irreplaceable files to another drive or burn them to a CD or DVD. After irreplaceable files have been backed up, you can rebuild the drive using Alsoft's DiskWarrior (www.alsoft.com US$79.95) to replace the damaged directory files or use Prosoft Engineering's new Drive Genius (www.prosofteng.com US$99) to rebuild them.

If the drive mounts and then disappears, reappearing only occasionally, you may have to go directly to the file recovery step. Firewire drives have two lights. One, usually green, indicates that it has power, and the other, normally red or orange, indicates that data is being transferred. If the red/orange light flickers on and off, your drive is still communicating with your computer and files can be recovered.

If the red/orange light does not come on, you will need to take the case apart and put the hard drive into another Firewire enclosure. Different companies make these and they are not very expensive (US$100).

If the drive inside is a 3?-inch and you have a PowerMac with an empty drive bay, you can install the drive there provided you have the technical confidence. On most PowerMacs this requires a Philips screwdriver and about 15 minutes, and is similar in complexity to installing a drive in a new Firewire enclosure.

I searched Google for instructions for installing a new hard drive on a Mac and found 400,000 different sites so instructions are available for whatever model you own. The only global cautions are do not drop or bang the drive, unplug the Mac before touching anything inside, and do not touch circuit boards without grounding yourself and eliminating static electricity that can ruin delicate circuits.

If the drive is transferring data (red/orange light blinks) but does not mount or you have installed it in your PowerMac and it does not mount, you will need to go directly to the file recovery stage and use a software-based file salvage utility.

There are two such tools for the Mac - File Salvage from SubRosaSoft (www.subrosasoft.com/thestore/

product_info.php?products_id=429 US$89.95) and Data Rescue from Prosoft Engineering (www.prosofteng.com/ US$89).

File Salvage recovers more than 60 different file formats, which is much more than Data Rescue, but it identifies the recovered files as numbers so it is a little difficult to tell if you have recovered the ones you wanted.

I have been told that Prosoft Engineering will release Data Rescue 2 next month and that it will recover more than 150 file formats. This will make it a superior product when combined with recovery by file name. If you still have not recovered your drive, run the recovery application if it can find the drive. If it cannot find the drive (and this takes courage) reformat the drive using Apple's Disk Utility in the Utilities folder. Then, even though the drive may appear to be erased, the file recovery tools can do their job.

I should point out that these recovery tools are oriented towards recovering documents, databases, images and films but they are not equipped to recover applications or operating systems. It is assumed that you have these on CD or can download them from the manufacturer's website. Nonetheless, this is a good reason for maintaining a database or document with all of your application serial numbers - it will save you the hassle of trying to find them all after a catastrophic loss scenario wherein you are using data recovery tools.