[plasticman]

I'm having trouble mounting an external USB hard drive. I have an 80GB disk that I've placed within an external HDD enclosure and until now it's been working absolutely fine. However, I mounted it and tried to backup files onto it and got beachballed. So, I shut down the computer, erased the contents of the external drive and reformatted it as a Mac volume (previously it was FAT32 for transferring files from my PC).

Now, however, I can't mount the disk. I ran disk utility and tried repairing permissions (whatever that means!) and received this error message:

---------------
Verify and Repair disk “disk1s3”
Checking HFS Plus volume.
Invalid B-tree node size
Invalid B-tree node size
Volume check failed.

Error: The underlying task reported failure on exit


1 HFS volume checked
1 volume could not be repaired because of an error
---------------

Can anyone tell me what may be happening?

Thanks for reading

[tooki]

The results you give aren't from a Repair Permissions operation, but from "Repair Disk".

If you have the opportunity to put the disk directly onto a Mac's internal ATA bus, do so and see what Disk Utility reports as the SMART status. (SMART doesn't work over USB or FireWire.)

Regardless, have you tried booting from an OS X CD/DVD and running Disk Utility from there?

If that, too, fails, then get a copy of DiskWarrior and see if it can fix it.

tooki

[plasticman]

Thanks for the information. I'll try booting from a OSX DVD and see if I can run disk utility from there. Is there any option in particular that I need to choose to run on the disk?

Diskwarrior costs $79, if I've looked it up right, so I'm a bit reluctant to use it.... I might instead connect the drive to a PC as there are different types of utilities that come with winXP and a format using a different OS may just jolt the drive back to being recognised by MacOS.

[tooki]

Hold on now... so do you have data on the disk you need to recover, or are you just looking to reformat?

Windows will not be able to do a thing with a Mac-formatted disk: it'll think it's blank or corrupted.

If you just want to reformat, do that with Disk Utility. You'd want to do an erase with zeroing if there's any suspicion of drive failure.

tooki