Currently Being ModeratedSep 17, 2013 6:42 AM (in response to baloney123456)
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It sound slike the external hard drive is no longer recognized in Mountain Lion.
I think it would be a good idea to reset your PRAM and SMC to see if that gets it to show back up.
- Shut down your Mac.
- Locate the following keys on the keyboard: Command (⌘), Option, P, and R. You will need to hold these keys down simultaneously in step 4.
- Turn on the computer.
- Press and hold the Command-Option-P-R keys before the gray screen appears.
- Hold the keys down until the computer restarts and you hear the startup sound for the second time.
- Release the keys.
After resetting NVRAM or PRAM, you may need to reconfigure your settings for speaker volume, screen resolution, startup disk selection, and time zone information. If issues persist, your Mac's logic board battery (not a portable Mac's rechargeable battery) may need to be replaced. The logic board battery helps retain NVRAM/PRAM settings when your computer is shut down. You can take your Mac to a Mac Genius or Apple Authorized Service Provider to replace the battery on the logic board.
From: About NVRAM and PRAM
- Shut down the computer.
- Plug in the MagSafe power adapter to a power source, connecting it to the Mac if its not already connected.
- On the built-in keyboard, press the (left side) Shift-Control-Option keys and the power button at the same time.
- Release all the keys and the power button at the same time.
- Press the power button to turn on the computer.
Note: The LED on the MagSafe power adapter may change states or temporarily turn off when you reset the SMC.
From: Intel-based Macs: Resetting the System Management Controller (SMC)
Currently Being ModeratedOct 19, 2013 6:27 PM (in response to sterling r)
There isn't any problem with my macbook, but problem with the Hard drive itslef. the usb connector port has shifted from its place making it difficult for the usb cable to reach there.
Currently Being ModeratedOct 19, 2013 6:44 PM (in response to baloney123456)
I have changed the micro usb lead
When you say "micro USB lead" what are you referring to specifically?
Most likely your problem is the SATA bridge card. External USB HD have an EXTREMELY HIGH failure rate on this part.
LIkely (very) your SATA card is fried inside the box for same.
External HD are very easy to diagnose. Bad USB cable (on commercial sold USB drives) almost doesn’t exist anymore.
External USB HD have 4 'parts' (not counting the HD internals)
1. USB cable (never an issue anymore, approaching 100%)
2. HD enclosure.....a plastic or metal box which cannot ever be an issue.
3. the HD itself
4. ....and last but not least is the epicenter of 'weak links' ,.....a SATA card/bridge that is connected to the HD inside the HD box, the size of a stick of gum, with SATA female on one side, and female USB on the other side, containing circuitry for data transfer between the SATA on the HD and to USB on the other.
While these bridge cards are better than they used to be, theyre still insanely unreliable.
There are 1000s of perfect external hard drives out there thrown away every year because people assume the "hard drive is bad" when really they could crack open the HD enclosure, remove the HD and put the good HD into a new enclosure.
See this video of the SATA CARD, its at 8:55min. http://www.youtube.com/watch?v=2pS_EDsP2KI
All conventional HD external are nearly 100% like the video above.
See pic below,..a (much larger) SATA card as found inside a typical HD enclosure ($20 ebay)
This is the nasty piece pictured below causing all the "crazy" activity seen on external HD, very odd behaviour, some have called it "haunted hard drive syndrome". Random ejects, random strange vanishing of the HD , especially in mid transfer of data.
the card attached to the TOP of the HD where it plugs in, that the SATA bridge connects to and is easily removed like unhooking 2 LEGO pieces.
Verify your HD doesnt show up in another USB port and another Mac, very likely your HD is fine, and only needs to be manually extracted and placed into a new HD enclosure.
Inside a USB hard drive, containing the HD and SATA card