Drive looks fine, but won't boot.

Question

Computer suddenly stopped recognizing the internal drive as the startup disc -- I get the ol' folder with the ? on it.
1. Started up from the tiger intall disc, selected the internal drive as the startup disc, no go.
2. Ran disc repair on the internal drive from the install disc, it found no problems but computer still won't start up from it.
3. Started up from my bootable backup on an external drive. Looked at contents of the problem internal drive, everything looks fine on it, I can access folders, run applications,all content is there, does not act as if it's failing (except of course that it won't boot.)
4.Did an Archive and install, which went flawlessly, but did not help, computer still won't boot up from the internal drive. Resetting the pram did not help, and it won't boot in safe mode either.
What should be my next step?

Answer 1

zanzen wrote:
The latest:
1. Erased the internal drive, loaded fresh OSX Tiger from the original disk. Opened and closed some applications, made some documents, restarted a couple of times, shutdown and started back up a couple of times. Everything working just fine.
You wrote zeros to the drive? You didn't just erase it?
2. Restored to the internal from external backup, using superduper. (and had superduper repair permissions on the backup before doing the restore.) Everything seemed fine at first. I restarted to the internal and it worked. Performed a few functions, tried restarting again and kablooey, back to the same thing; pauses on the flashing ? folder for a few seconds, then goes to the white apple screen, and that's as far as it will go.
3. Tried using both option restart, and restarting from the startup disk system pref., neither works. I noticed that on option restart, the the icon that comes up on the screen for my internal does not have the name I gave it, just a little 'diamond G' sort of symbol under it, which I assume is the maker Seagate's symbol. My external's icon does have its assigned name. In the startup disk preference and on the desktop (when I'm up and running from the external), the internal's assigned name is there. So it's only when doing an option restart that the internal's name is missing.
The last backup of the internal was done 3 or 4 days before this startup problem began, and the computer was used plenty during those days (family of five, with that many user profiles on the computer), so if there's something on the backup that is causing this problem, it's strange that it didn't cause any problems during those few days. And also strange that it doesn't cause a problem for the external drive, only for the internal.
How many restarts during those 3 or 4 days? How many times have you successfully booted from the external and what did you do while booted from it?
I'm wondering if the cause of the problem was backed up to the external but not the problem itself. Maybe the problem is triggered by start up / shut down but only then affects the next start up. I'm not sure this really makes sense of everything, though...
Can you examine the system logs while booted from the external, maybe? That is, use /Applications/Utilities/Console to open the internal's log files - especially /var/log/system.log and friends. I don't know this will do any good. Presumably, nothing is getting written here during the failed start ups but maybe there is something which would give a clue from the last successful start up and shut down.
- cfr