here's what you should do.
-open up a new finder window
-navigate to wherever your applications are saved usually your applications folder....
-open up utilites and then navigate to disk utitility
-click on the disk that you're using and then press repair permissions then reboot and see what happens
-believe it or not this is a fix for alot of things surrounding macs
if that does'nt work
-have you installed any new apps lateley?
-any new .kexts?
-any intel only parts
-has someone else used your computer?
-did your computer come in contact with a magnet?
-is your computer used as a server or in a public place?
-are you prepared to format your hard drive if nessescary?
-did you get any new peripherals?
-hardware?
-any parts on the inside or outside of your computer?
-spill something on your computer?
-cause physical trauma to the computer itself eg. dropping , kicking , punching , throwing , hitting biting , throwing things at the case , making it fall , pushing it around etc.
-have you moved homes recently?
-do you have kids?
if you ask yourself those questions above i'm sure you'll find what you're looking for.
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