Upon pushing the start button my G4 rings like a phone before the boot up sound and then proceeds to stay on the white screen with the apple displayed and the circle spinning below the apple. Nothing else happens. I have tried to reinstall with startup CDs, but the machine won't complete the process but says there are errors in the reinstall and to try again.

The White Screen with the Apple is the phase where the OS is atttempting to check (and repair, if possible) problems with the file system. If it stays there forever and a day, it's most likely that you have a problem with your hard drive (hardware failure).

Check you SMART status in Disk Utility when booted from the installer DVD:
http://docs.info.apple.com/article.h...n/duh1896.html
Try repairing the boot drive when booted from the installer DVD:
http://docs.info.apple.com/article.h...n/duh1008.html

Try a more robust disk repair utility if that fails, something like DiskWarrior or TechTooPro.

Failing that, it's time for a hard drive replacement, most likely.

sounds like a bad HD. did you reformat?

Thank you for your quick reply.

The DiskUtility on the OS X Installer CD gave the following error message:
Underlying task reported failure.

Error code -9972

I can see that my data is on the hard drive. Is it possible to back up my data to a network in some way when I can't get the machine to boot up?

command-t or only t, during startup put your computer in target mode.
when connected to another computer via firewire, your mac shows up just as an external harddisk, and can be repaired, for exaple with diskwarrior.

Hello,

Yep, that is the way to go... have the computer behave like an external hard disk. Older Macs used to call it "SCSI DISK MODE", and the newer ones Target Disk Mode. I don't think the new Intel computers support it though.

The bigger lesson, however, is not to wait until a situation like this to have backups handy. While you may still see the files, if the directory structure is damaged, you may not be able to retrieve them.

After rebuilding your computer, build a solid backup strategy. Stick to it. And then enxt time, you will not need to be worried about this.

Christian

The same thing just happened to me. I took it to a mac certified repair guy and he ran disk warrior on it. I got it back and it booted up once (I was able to backup) and now it does the same thing. Do I need a new hard drive? If so where do I get one? Thanks!

First try wiping the hard drive and reinstalling Mac OS X. Failing that, I'd say you need a new hard drive. You can probably get one at a local computer store or an online source such as newegg.com.

Thanks! I'll try that and cross my fingers