This may be a hardware issue , but lets run through all the tests and repairs we can make .
First , Please what mac do you have ? so I can get the reset info .
below is the steps to repair the mac hd first off common to all macs .
Lets run though some basic repair checks .Repair Mac HD , Check Permissions with the OSX Startup volume.To check for disk errors and possibly fix issues with the Mac HD volume and other Partitions .Please run a Mac HD drive repair ,and Repair Permissions of the Mac HD startup volume .Carry out repairs twice and then verify on both Mac HD and other partitions if any , also do same for your external HDD's if you have any , in turn .Review this video to become familiar with the below procedure ..http://www.youtube.com/watch?v=MFv3h7MVX4A&feature=relatedDisk Utility1 Start from your Mac OS X Install disc: Insert the installation disc, then restart the computer while holding the C key.2 When your computer finishes starting up from the disc, choose Disk Utility from the Installer menu.(In Mac OS X 10.4 or later, you must select your language first.)?Important:- Do not click Continue in the first screen of the Installer.If you do, you must restart from the disc again to access Disk Utility.3 Click the First Aid tab.4 Click the disclosure triangle to the left of the hard drive icon to display the names of your hard disk volumes and partitions.5 Choose your Mac OS X volume.6 Click Repair. Disk Utility checks and repairs the disk.If errors are found please run the check twice .Report any errors in displayed RED to me .Tip:- Always start up your computer from an Install or Restore disc when using Disk Utility to verify or repair your startup volume.**Perform Disk permission repairs while Booted to your Mac HD as normal**.Please run repairs on all your Mac HD partitions and disks.Choose in turn the drive name from the left hand list , and use repair .Run repairs twice if RED errors where found , check to see if they are now cleared.Using the Repair Privileges UtilityFor Mac OS X 10.2 or later, open Disk Utility found in the Applications/Utilities folder.Select your Mac OS X startup volume in the column on the left of the Disk Utility window, then click the First Aid tab.Click the Repair Disk Permissions button.Please wait while the Mac HD is checked.If errors are found please run the check twice .Report any errors displayed in RED to me .-Permissions DefinedMac OS X incorporates a subsystem based on a UNIX-style operating system that uses permissions in the file system.Every file and folder on your hard disk has an associated set of permissions that determines who can read, write to, or execute it.Now run some tests with your software and see if there's a difference ?-You can also try this more simple step to try to correct issues :-Turn off the Mac .Power on the Mac .Hold shift on the keyboard using a USB keyboard , while powering on the Mac and booting , boot to safe mode.Once booted to safe mode , restart and boot as normal .Full details here :-http://support.apple.com/kb/ht1455This may fix minor issues but it is best to run a Full Mac HD repair from the OSX DVD installer disk , use the OSX disk that goes with your current OSX install ..I hope this helps .if you still have issues or are unsure please let me know .
Please report errors ,
If there is a problem we have a few options to go yet , including resets , archive and install , please do not jump ahead though .
Also are you backed up ?
Thanks, XXXXX XXXXX seems to be fine now since I first contacted you. It turns out we seem to have had some power fluxuations in the neighborhood, along with an outage I was not aware of, that coincidentally came back on while I was trying to find out what was wrong with the switch.