Bad Blocks

[Smokin78]

Don't know if this has been dealt with before but, I ran the latest version of Nortons on my G4 with OSX.2.6 and when checking the media, it tells me there are 'Bad Blocks' that have become demagnetized and are not capable of storing info.  Nortons is unable to fix the problem and was wondering if there is any way to cure this problem?

[beacher]

Hey Smokin', I've had that same problem on my ol' G3, for about 3 years; as far as I know, it can't be fixed, and although I've had people tell me that it can cause problems, so far it hasn't (keepin' my fingers crossed!).  Some folks have said that if you reformat the hard drive, and then reload everything, the problem may be "cured", but no guarantees. . . So I've just lived with it, and kept my fingers crossed.  It's just one more of those things that MAKE me conscious of making backups of my data. . .

[JohnKentucky]

Well..first thing you need to do is throw that Norton's CD away. It's a well known fact that Norton's doesn't play well with OSX.

Even when I called Apple last week for a HD issue, they asked if I had Norton's installed. Please..do yourself a favor...get rid of it. DiskWarrior 3 is a better HD utility..AppleCare even suggested I use it.

[bil207]

I suggest backing up all the important data on the drive. Most of the time but not always the bad blocks can be mapped out using a disk utility to reformat.

The best method that I know of to map out bad blocks on a hard drive is to reformat using Drive Setup in OS 9.xx.
Start up from an OS 9.xx cd and choose the option to zero all data. When you reformat using this option it usually takes approx. 1 hr per 10GB.

Disk Utility in OS 10.2 also has the option to zero all data when reformatting. When I used Disk Utility to reformat a 120 GB. drive with this option selected it finished in about 15 mins. so I'm a little skepitcal of it doing what it claimed.

If the drive only has a few bad blocks that are successfuly mapped out it should be alright, if it has a bunch of them I would replace the drive.

[kelly]

I don't know if the new Norton has a bug or not.

If you really do have Bad Blocks. I agree with Bill.

Drive Setup: Checking For Bad Blocks

http://docs.info.apple.com/article.html?artnum=24764


But then you guys have everything backed up.

[ljocampo]

Drive 10 will also check for bad blocks except they call it "Checking Media."  This is very common thing, most hard drives come straight from the factory with at least some bad blocks due to their manufacturing process.  Just map them out with the utility of choice, such as DW3, Norton under OS9 only, TTP, or apple's own and you'll never even know you have them.

[tacit]

" Just map them out with the utility of choice, such as DW3, Norton under OS9 only, TTP, or apple's own and you'll never even know you have them."

Norton and other utilities can't actually map out a bad block. They all perform some sleight-of-hand to "fix" bad blocks; Norton, for example, creates an invisible, locked file that sits on top of the bad block, marking it as being in use.

The only way to map them out for good is to reformat the hard drive using the "Zero all sectors" option. This will update the bad block list stored on the drive itself and map the bad blocks to spares.

If the drive format fails, the drive has too many bad blocks to be remapped, and the drive should be replaced.