When is it time to reformat a hard drive?

I was listening to a recent episode of a friend’s podcast earlier this morning. He was discussing Macworld and his experiences there. Unfortunately he had a bit of trouble with his hard drive. I still have not finished listening to the podcast, but I just had to stop to write this blog post.

The back story of his troubles at Macworld involve a hard drive that developed some catalog errors that could not be fixed with Apple’s Disk Utility.

While many of my readers understand what I just said, some of you are now ready to quit reading…don’t! Bear with me and I will explain this in a way that is easy to understand.

It often helps to compare an item to something familiar to the reader. For those of you who are over 30, continue reading. For anyone under thirty, read along, but you may have some problems visualizing this analogy.

We are going to compare a computer hard drive to the local public library. When you enter the library, you see row after row of bookshelves. In the old days (probably less than five years ago), every library had a set of cabinets holding index cards. Those cards helped the user find the books stored in the library.

Our Macintosh computers have something similar. Apple Inc. developed the Hierarchical File System (HFS) for our hard drives. It keeps track of where the files on our computer are stored. In essence, it is the card catalog for our hard drives.

That catalog file is used all day long as our computers operate. When everything goes well, our computers hum along and everyone (and everything) is happy.

Let’s go back to the card catalog in the library. At the bottom of each drawer was a little knob. Attached to the knob was a long metal rod that screwed into the back of the drawer. Each card in the drawer had a hole in the bottom and the rod ran through the holes. When new books were added to the library, the librarian would remove the rod from the drawer, insert cards for the new books and then carefully replace the rod.

Now, occasionally a drawer of cards would somehow spill. The cards would get out of order. In order to make the card catalog fully useful again, the cards would have to be re-filed into the proper order.

When your computer suddenly looses power, its HFS file catalog may not have time to update the catalog properly. It is similar to someone dumping a drawer from the library’s card catalog. While parts of the hard drive’s file catalog might be working, the data stored in a particular area can be “messed up.”

The tool we use to fix the computer’s file catalog is Disk Utility. It is stored in the Utilities folder inside your Applications folder.

While Apple has built a world-class tool, it cannot fix every hard drive problem. So, third party companies have stepped in and made some very powerful (and expensive) tools to fix the problems that Disk Utility cannot fix.

So why doesn’t Apple just make Disk Utility more powerful so that we don’t have to buy these other programs? It’s time for another analogy. This time, we are going to think about the inner tube that is used in some tires. My mechanic will patch the inner tube if he does not have a new tube, but he warns about driving with a patched inner tube. When get a hole in the inner tube of my bike tire, I get the same advice at the bike shop.

While Apple’s Disk Utility can fix smaller (but important) issues and while some Apple Store Genius Bar personnel may suggest and advanced utility, the usual recommendation is to back up the drive and reformat it.

Programs like Alsoft Disk Warrior and Micromat TechTool Pro are, in essence, like the patches that can be applied to an inner tube. They fix the problem and everything should be fine--for a while. If you put the tire under stress, the patch will fail. If you put your hard drive under stress, these patches will fail.

Disk Warrior and TechTool Pro are expensive applications, at about $100. They need to be updated every time Apple does a major software update, for example, from Mac OS X 10.4 to 10.5. You can cause real problems if you attempt to use an earlier version on a more recent OS version.

Most people do not need these programs. Instead, spend the money on a back-up drive and keep your software up-to-date. Then, when you run into a problem, you will have the tools needed to do one last backup and then reformat your hard drive.

If you are having problems with your computer, remember us at Bob LeVitus Consulting. We can give you a hand in doing that last backup and we can help you through the reformat and install process. We can even help you attempt to recover data from a failed drive or we can help you get your drive to the professionals at DriveSavers (and get you a discount too). Just send us a message or give us a call at 408 627-7577.

--Pat