I'm using the disk utility to verify the HD and it throws up this message


Verifying volume “Macintosh HD”
Checking HFS Plus volume.
Checking Extents Overflow file.
Checking Catalog file.
Checking multi-linked files.
Checking Catalog hierarchy.
%)
Checking Extended Attributes file.
Checking volume bitmap.
Checking volume information.
Volume Header needs minor repair
d.",1)
Macintosh HD
Error: The underlying task reported failure on exit


1 HFS volume checked
Volume needs repair


but the "repair disk" button is greyed out.

I'm pretty sure i've got it to this point before and it asked for the install disk but it wasn't to hand so i cancelled, came back to it now with the original install disk but it just wont let me repair. any ideas? Thanks, Nick.

You can't repair the disk because it is currently running the operating system.
There are two choices:

1. Insert the Installation DVD that came with the computer. Restart and hold the C key immediately after the start chime to boot from the DVD. Release the key when the progress indicator appears below the Apple logo. When you get to the Language Chooser, pick English and click the continue arrow at bottom right. This will take you to the Installer. Quit the Installer and go to Utilities in the menu bar. Choose Disk Utility and run Disk Repair. Restart the computer as normal when you are done.

2. Go to: http://applejack.sourceforge.net/ and download a free copy of Applejack. Read the instructions carefully and install it. You can now run Disk Repair by starting up in Single User mode (hold command & S keys until you see a black screen with white type on it). Type: Applejack and press return. Type: 1 and press return. When it's done press return, R and return once more to restart normally.

You could also type: Applejack return, A, return, to have it do all maintenance tasks in one go.

your fix worked first time (used the install disk) :thumbsup:
I owe you a pint, thanks :bigsmile:

Glad it worked for you.