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My late 2009 unibody MBP won't boot. I have already booted in single user mode, ran fsck -fy until I get no errors. But when typing 'exit' or rebooting in verbose mode I see, after fsck runs:

Failed to issue COM RESET successfully after 3 attempts. Failing... disk0s2: no such device disk0s2: media is not present.

The HD appears to be working, because when booting in single user mode I can run fsck successfully and can browse the HD, listing directories, inspecting files.

I just don't know why the OS can read the disk but reports it as 'not present' when booting.

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up vote 1 down vote accepted

That's either a disk on it's way out or something has been corrupted and the OS is having problems mounting the drive.

Do you have your system disk? If so, you could try booting into is by holding the C key while booting and run Disk Utility, then do a permissions repair and a disk repair if you can.

What fsck command did you enter? fsck -f ? If not then you should try that too.

If you can get into single-user mode then you can run the following command to repair permissions:

sudo diskutil repairPermissions /

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Yes, fsck -fy. I don't have the system disk right here, that's the next thing to try. But supposedly fsck should do the same as Disk Utility. – Marco Mustapic Feb 7 '11 at 19:38
See edit for disk permissions command – conorgriffin Feb 7 '11 at 19:54
Can't launch diskutil in single-user mode, bould I could repair the disk booting with the system disk. Although it got corrupted again some minutes later. Third HD for this MBP. – Marco Mustapic Feb 8 '11 at 1:01
Third HDD? Yikes, well I'd recommend you get an SSD. Do you carry it around a lot? The biggest thing to be mindful of is moving it when you close the lid. You shouldn't move it until the status light has gone from on to a slow pulse – conorgriffin Feb 8 '11 at 1:04

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