Hi -- The best place for this kind of question is the support boards at Apple's website -- <http://www.apple.com/support/>, bit I'll give you quick rundown here. The Apple boards are very friendly and have answered a heck of a lot of obscure questions very quickly, much less straightforward ones like this. I would recommend AGAINST using Norton Utilities on OS X. Look at the Apple boards and you will see way too many horror stories of Norton fragging hard drives. You _definitely_ can mess things up using utilities meant for OS 8 or 9 on OS X, as they are totally different environments and the utilities can get confused while rummaging around your system. That notwithstanding, the Norton Utilities that are _designed for_ OS X have developed a reputation for messing up otherwise sound drives. Norton dropped the ball with OS X, and has lost a lot of trust among Mac users. (Norton AntiVirus is about the only Norton product I would -- and do -- use on OS X.) I personally use DiskWarrior 3 by Alsoft, which examines your hard drive and writes a completely new directory from scratch, rather than trying to repair a damaged one. It does not defrag, but it is my understanding that with Unix-based OSes (such as OS X), defragging is not nearly as important as with Windows or old Mac OSes. Supposedly they do so much writing of temporary files and such that even if you do defrag it's fragged again in about ten minutes. What Disk Warrior does, (besides saving your bacon if your disk gets corrupted), is optimize the disk's directory, which does seem to speed things up a bit. If you still think you need to defrag, a pretty good utility is Drive 10 by Micromat. TechTool, by the same company, is also a popular utility, but I don't know if it defrags or not -- worth checking out though. BTW, pretty much any utility that is going to fix a messed up hard drive is going to make you boot from a disk other than that drive. You can either boot from the CD or boot from another hard drive, but (on Mac at least) they pretty much unmount the drive they are going to fix, and you can't unmount the boot drive. Steve On Jan 30, 2004, at 9:44 PM, Joshua Hmielowski wrote: > any one familiar with good defrag software for osx? > I currently have used Norton system works 9.2 and that worked before. > However , if I have major problems on my hard drive, > it has to be booted from the disc. For what ever reason I can run it > from the > disc but I get an err every time and it does not fix anything.