Thank you in advance for any suggestions. I'm a bit bewildered (panicked). I have had this Powerbook for a few years without any trouble. I'm a relatively simple user and haven't added any hardware or recent software. Since yesterday PM it has failed to reboot. I have OsX Tiger and have kept it updated. When restarting it gets hung up and won't go to the Os X startup. Occasionally, it will go to a blue screen and an apple folder icon appears in the middle, otherwise it just runs with the grey field and the the circle icon endlessly rotates. Occasionally, it will turn itself off. When I boot with the Os X Tiger disc and go to disc utilities and verify the disc I get an error: "Invalid node structure". When I use the repair disc function I get:
"Invalid node structure"
"rebuilding Catalogue B-tree"
"Volume Macintosh HD could not be repaired"
"Error: the underlying task reported failure on exit"
"1 HFS volume checked"
"1 Volume could not be repaired"
I've never had problems with this computer . I've installed no new software recently and no new hardware at all.