Corrupted MBR of my external hard disk

methu

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Jun 1, 2010
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the MBR of my external hard disk is corrupted and as such, I can't access it. When I plug it into my laptop, it's recognized as a USB Mass Storage Device when I try to safely remove it, but there is no drive letter assigned to it. All softwares I have used show the drive to have 0MB but it's a 250GB drive. What Can I do?
 

methu

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thanks for the suggestion. I really appreciate it. I tried almost all those results and it still dun work. I tried using the fixmbr and fixboot commands but they all dont work because I'm told that the device attached to the computer is not functioning...... Any other ideas??
 

Paperdoc

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The fact that a USB external drive is recognized on the USB bus does not prove that the drive itself it OK. It only proves the USB bus in your computer can communicate at least partially with the controller board in the external unit.

One of the better ways to start diagnosing a troubled external drive is to remove the HDD unit itself form the external case and then mount / connect it internally in a desktop machine where you can test it. Two things you must watch out for, though. Doing this will void the warranty on the external unit, so if it's still under warranty you should contact the manufacturer instead. Secondly, what you will need to connect it inside a desktop unit depends on what type of HDD unit is inside the case. If it is a small portable PC type of HDD unit its connections and size may require an adapter to get it set up in a desktop machine. And of course, you'd need access to a desktop machine!

If you can move the unit this way it eliminates extra hardware that may be malfunctioning. If that is all that's wrong - the external case's controller is faulty - the HDD itself may function perfectly when inside the desktop. But if that does not happen you probably can get HDD diagnostic utility tools by free download from the manufacturer of the HDD unit (not the maker of the external drive system). You can use these to test the HDD and determine whether it can be repaired easily.

Oh, there's one other type of malfunction that can be fixed easily. On some occasions the connections inside the external drive case to the HDD unit are poor, and simply disconnecting the drive and re-connecting it a few times might clean that up so it works again. That's if you are really lucky!
 

methu

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Thanks paperdoc for your contribution. I checked on all your suggestions an it still doesn't work. It seems the hard disk is actually done for. It is shown as 0MB and trying to fix the MBR gives me an error message. I wish I could somehow retrieve some of the data on one partition....... Any ideas??
 

Paperdoc

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Check out a third-party data recovery tool called GetDataBack NTFS. (There's also a version for DOS-Formatted units.) You will need a spare hard drive on which to place copied files if they can be recovered. You must pay for it to acquire and use it, but they have a unique free trial system. Go to their website and you can actually run their software on your drive - it can take a LONG time to work! It will do its complete analysis of your malfunctioning drive and finally show you all the files it can find and recover. You can even open test files to examine their contents. IF you are happy with what it can do you pay them their price and it downloads and installs itself on your computer - you now own a licensed version - and it completes the task of copying everything it can to your spare drive. On the other hand if the tool cannot do what you need, you don't pay and just back out. It leaves your faulty drive untouched so you can try another tool.
 

aviiandevil

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Jun 23, 2011
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i had the exact same problem.. itz something WIN 7 / vista does it to the drive .. mine is win 7 it messed it up and it didnt even work on Linux. But i plugged it in Win XP SP2 32-bit. and it is working fine.. in win 7 when i ran HDD regenerator it said the drives MBR is damaged but in XP itz fine.. looks like something big with Win 7...
 
It appears to me that the drive has powered up in "safe" mode. That is, after it performs a self test of the components on the PCB, the MCU attempts to retrieve the runtime firmware from a reserved System Area (SA) on the platters. If there is a problem with any of the modules in the SA, then the drive powers up with 0 LBAs.

If your drive is a Seagate, then sometimes there is a low cost, DIY fix.