error message -600

Hi all! I'm new - and having some real trouble with my macbook lately.

I notice that if I leave my computer idle long enough for it to go into sleep mode, the screen goes blank w/ backlight ON, but will not come back to life when I run my fingers across the touchpad or hit any keys. So I have to turn it off, turn it back on, and re-load my browser to get back where I was. Very annoying. I took it genius bar and they said nothing was wrong and that I just need to change my settings in sys pref.

So I go to do that today and system preferences won't open. It shows up as open on the dock, but no windows pop up anywhere and when I force quit it (ctrl + opt + esc), it gives me an error message of -600. Its doing the same thing for iTunes, same message and everything.

Can anyone help me out here? This computer is about 3-4 years old and in really good shape. I'd hate to lose it over some stupid error message (when I throw it against the wall!!!).

Any info is greatly appreciated!

Your hard drive could be acting up or getting ready to fail. But that's not a given.... Try running the Apple Hardware Test on your computer to see if it comes up with any errors. If everything checks out OK with the AHT, run Disk Utility from your install DVD and do a verify and repair on the hard drive. That means booting from your install DVD first and then go to the top menu "Utilities", "Disk Utility". Highlight your hard drive on the left side and then select Verify and Repair.