View Full Version : Repairing volume header after lightening strike

25th February 2008, 06:59 PM

I'm just wondering if I could pick the brains of the intelligent folk that are MacTalkers.

My house or somewhere very nearby was struck by lightening at the end of last year and my 24" 2.8GHz iMac was hit! After spending 22 days in the shop waiting for parts the power supply, logic board and video card were replaced. I also upped the memory to 4GB at this time (mid January).

All was great I had my Mac back and it was a tad faster.

However, about 10 days ago performance on the iMac had slowed a bit so I did a restart. After restart it didn't boot! All I got was a circle with a line through it! So I put in the original install disk did a hardware check and all was reported to be good. I then ran repair disk in disk utility and it found and fixed a minor volume header error. I was a tad concerned but all seemed well again.

Then just this weekend (2 days ago) things were a bit slow so I tried a restart and it wouldn't restart it hung after quitting all apps. So I force shutdown, then rebooted and got nuthin', just a grey screen. So I once again ran repair disk this time from the Leopard install disk and once again it found and fixed a minor volume header error. Hmmmm.

So I'm just wondering if anyone can shed any light on this situation for me. Is the hard drive dying? SMARTReporter says it is fine. Could it be the RAM? Or could it be a software issue? It must be about 2 weeks ago that I upgraded to 10.5.2.

Any thoughts/assistance would be greatly appreciated.

Thanks in advance,
LandLord (long time lurker)

25th February 2008, 07:08 PM
It certainly sounds like the drive is on the way out, or it has bad sectors in the area that the header is written.
Two solutions. First, obviously, is replace the drive. Storage is very very cheap.
Second, clone your drive (to backup) and do a low level format writing zero's across the drive. This will mark any bad sectors as not available for writing. Downside is that any damage that might have been done by the surge may result in more bad sectors being created by a badly aligned head causing further data loss.

25th February 2008, 07:27 PM
Thanks for your reply astr0b0y. Solution one sounds like the top choice considering the downside of solution two. I should have mentioned it is a 1TB drive. I also should have mentioned that it is still under warranty. Does anyone think that a service centre would replace the drive after two volume header repairs or should I wait for some more serious symptoms. I am backed up with time machine to an external 1TB drive so I'm not hugely concerned about data loss.

26th February 2008, 08:52 AM
You know what I would do?

Swap the roles of the two for a while and see if the issue persists.

ie The system running off external drive, backup to internal.

ie See if a system running off external drive fouls up like you have described.