I was transferring large number of files from computer to one of my portable hard disks by copy & paste method when it malfunctioned.

Now I cannot use this external drive. There is nothing important on this drive and is not a SATA drive, although is USB 3.
Please find below details of the errors encountered:

External Portable Hard Disk connects to computer successfully.

• External Drive shows up in Windows Explorer, but has just a drive letter and no details, and when I try to acces it I receive a message: Please Insert a disk into drive J.
• External Drive shows up in Disk Management as a drive as unallocated, with size of disk (i.e. 465.76 GB Unallocated).
• At the moment I cannot use the drive but would like to..
• Can disconnect external hard disk successfully by using: Safely Remove Hardware.
• Name of disk drive (i.e. Samsung P3 Portable USB Device).
• Would the Master Boot Record be corrupted/damaged?, and can it be repaired for further use?
I feel maybe it can be repaired. Maybe the Master Boot Record is corrupted. Although the computer connects this drive nothing can be done with it at present.

Can anyone offer any solutions/advice and/or help.

Thank You David

1 Year
Discussion Span
Last Post by rubberman

The good news is you used copy and paste. That means you didn't lose files.

As to the external I'd try the last hurrahs before last rites. To me this means.

  1. Use a zero fill app for the external. This will take some time. After, partition, format and try it again.
  2. You didn't reveal what the PC host was. I find desktop front ports to best be forgotten and laptop USB ports to only be used when on AC power for USB powered drive.

As to the MBR, I see google searches find how to rewrite just that. But that won't bring it back to operation, that's for the partition and format to bring it back.


Unfortunately, Windows hasn't always handled buffering of large amounts of data when reading/writing to external drives very well. You don't mention which verion of Windows you are using, but I would guess XP? Linux? Never had such a problem (I regularly read/write/copy/move 100's of gigabytes of data without issue). Windows? Not so lucky. This isn't a screed against Windows (ok - it is), but this is not an unknown problem. As rproffitt said, at least (as you said) you did a copy/paste, so the original data should be there. There may be a problem with data that had previously been stored on the USB drive. You should be able to run the Windows disc recovery tools to fix that, though you might lose some data.

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