You are now privy to the open secret that Norton can be a fraught proposition in versions above 3.2.x and with HFS+-formatted drives. DiskWarrior 2.1.1 (Alsoft) is much more certain as a file directory defragmenter/rescuer, and will rebless your System Folder at need. It is important to remember, however, that DW is a file utility, not a disk utility, and will not do anything unless your disk partitions and other logical structures are intact. However, the inbuilt Apple utilities can ensure this latter condition, and DW will fix the boot blocks after it has fixed the disk directory.
If you are in deep do-do because of corruption of the disk's logical structures, and whether or not the existing formatting was done by Drive Setup or by a third-party utility, you should aim to acquire a disk utility program with an informative GUI, especially if you have several Macs to care for. LaCie's Silverlining (v.6.4.1 to 6.5.4), InTech's HD SpeedTools, FWB's HD ToolKit and ATTO's ExpressPro-Tools will all work, and it is a Good Thing (and less taxing of your memory) to use one disk formatter throughout your collection. Silverlining is bundled with LaCie drives, but obtainable on the Web from expectable sources. The latter three are commercial utilities, but obtainable on eBay and elsewhere. I use Silverlining on about 100 HDDs without any unsolvable problems.
It is preferable that you rebless a System Folder by dragging either Finder or the System suitcase to the desktop, closing the System Folder, and then dragging the Finder or System back onto the closed System Folder.
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