[Harvey]

For 2 days running my MacBook Pro (circa 2008) has not booted and flashes the prohibited sign similar to no smoking or no entry. . . . the circle with a bar diagonally through it. My only recourse was to boot from my installation disk. I have used disk utility to check and fix permissions and disk sector. Nothing seems to work. If I stay in sleep mode the mac with continue to operate until my wireless connection is somehow dropped. Check the router on my other computer and that proved to be fine. the only other symptom that I've noticed is a hotter than usual laptop bottom. Also I did replace the HD 6 months ago from the standard size to a 500gb. If anyone has a similar problem or a fix, I would appreciate hearing from you.

Harv

[Spheric Harlot]

Gut reaction:

Your hard drive is dying.

[reader50]

There's something wrong with your OSX install on the drive. The drive hardware is probably OK - you'd see a blinking folder if no drive could be found.

Do an upgrade install, preserving users and groups. That should bring your Mac back to life. And I hope you are backed up, in case anything goes wrong.

[Harvey]

Is there a software fix? Would a program like cocktail be useful?

[Waragainstsleep]

Any software fix would likely be a temporary measure. Your best bet is to back up your data and wipe the drive clean. Put a fresh install in place.