Re: "No" symbol after restart

It can't find a startup drive/OS. Something got corrupted (most likely) or the startup drive has failed.

I would startup off of the the installer disks that came with your Mac. You can then try repairing your startup drive using Disk Utility (found on the installer disk pull down menu).

If that doesn't fix the problem (try restarting again of the internal drive after repair) just start up off of the installer disks again and do an "archive and install" to replace your existing OS with a clean install (you will need to run all the updates again afterwards). Be sure to turn on the options in the Archive and Install options to save your files, users, etc (can't remember the exact terminology).

Its always a good idea to repair your permissions and repair the drives (using Disk Utility or a 3rd party application like Disk Warrior) before and after running any major software updates and/or every month or so, to help prevent problems from occurring in the future.

Tony!