External HDD not recognized

By hhmartinjr ·
My laptop is not recognizing my external hard drive, which was drive E:// It's a USB, plug-play device with external power source. Over the past few days we've had several storms with power outages. I don't know at which point the computer, (OS Windows XP Pro)which continued to run on battery, decided not to recognize the device.
any clues on how to reconnect?

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Denial of power to any hard drive can be disastrous ...

by OldER Mycroft In reply to External HDD not recogniz ...

Any hard drive whether internal or external that is suddenly denied AC power, can be badly damaged at worst, at best the damage would be limited to whatever files were being read or written at time of power outage.

I'm rather worried that you comment on "several storms with power outages. I don't know at which point..." - I would have shut the system down after the first power outage and disconnected the external drive to examine for obvious signs of damage from any possible spikes or surges.

Since the power outage may have also damaged the usb connection, I would suggest you connect this external drive to another computer and see if it can be detected. I'd also suggest you try plugging something else into the usb socket and see if it still works.

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Also look in Drive Management

by OH Smeg In reply to Denial of power to any ha ...

And see if the drive is showing there even if it is coming up as Blank requiring formatting.

If it is claiming that it requires Formatting the Partition Tables have been damaged and they require fixing with a Data Recovery Application.

Of course if the drive isn't present in Drive Management either the USB Interface in the enclosure is damaged or the HDD itself has been damaged requiring replacement of the damaged part/s.


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drive management

by hhmartinjr In reply to Also look in Drive Manage ...

OK, this dummy asks: How do I get to "drive management?"

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Route to Drive Management ...

by OldER Mycroft In reply to drive management

Start > right click on My Computer > Manage > in the left hand column under the 'Storage' heading, you click on 'Disk Management':

The right hand column is split horizontally - the hard drives are summarised at the top and detailed at the bottom.

Does your external drive appear in this dialogue box? Post back.

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denial of power

by hhmartinjr In reply to Denial of power to any ha ...

you're right. I should have disconnected. However, as to damaging the usb connection, everything else running through my usb hub, which has it's own separate power source, is running perfectly. That includes printer, mouse, itunes connection etc.
The external HDD turns on, or at least shows an ON light, but doesn't do anything else.

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Does the HDD make the right sound?

by techrepublic In reply to denial of power

Virtually all HDD I have used make some sound, especially when starting. Is the HDD making the right sound? If not then you probably have a damaged HDD.

Check the USB information regarding the connected devices. Maybe the HDD is working correctly but the file system is damaged to the point that is not even recognized and so it is not mounted.

If the USB circuitry is damaged, the HDD it self may still be good and you may be able to take it out and put it in another USB external box.

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HDD sound

by hhmartinjr In reply to Does the HDD make the rig ...

it never made a sound even when it was working properly. anyway, have taken it to the shop where I bought it, and they have some good techies there.
It is under warranty, at least the box is, but I hope they can save the data.

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Delete Usb Drive Letter via Registry to Remove Conflict .

Any changes you make in the registry could make the computer unstable or UN-operable.

In Windows operating system especially Windows XP, when plug in external USB or FireWire mass storage device such as USB key, flash drive, portable harddrive, the drive is not been assigned a drive letter by the system, hence the USB drive or FireWire drive is not showing in Explorer and no AutoPlay or AutoRun window pops up, although the device has been detected, in Safely Remove Hardware (show device but with no drive letter) wizard. The cause is probably due to ?stupid? behavior of XP where it won?t find an available letter from the free letters pool when the USB or FireWire external drive which has previously mounted and assigned a drive letter is been inserted to computer USB or FireWire port again, but that previously allocated drive letter has been taken up and used by another storage devices. Another possible reason is all 26 letters in alphabet has been used, but this situation is rare and unlikely.

There is a solution to USB or FireWire drive not showing in system error. However, the disconnect conflicted storage device to free up the drive letter fix may not be practicable or usable by some, such as computers which are on a network or system running data transfer activity to all its drive assignments continuously flow without stopping, and thus disconnect or reassigning any mapped drives, networked drives, removable drives or other storage drives is not an option.
In this situation, there is another workaround hack to fix the no USB or FireWire drive issue. The workaround fix relies on the registry tweak below to change the drive letter that has been previously assigned to the mounted USB or FireWire portable mobile flash or hard disk drive. Or if users wish, can opt to delete any reference to the detected drives by the device so that when the storage device is plugged in again, the whole drive letter assignment will be start from fresh, and clean.

1.Login to Windows as an Administrator.

2.Open Registry Editor by typing regedit (or regedt32.exe in older Windows prior to XP) in Run command of Start Menu and then press Enter.

3.Navigate to the following registry key:

4.Optional step which not required in Windows XP or later, right click on MountedDevices, then select Permissions. You can also click Permissions from the Security menu.

5.Optional step which not required in Windows XP or later, check the option to make sure that Administrators have full control to the registry key. Change and revert back this setting when you are finished with the reset of the steps.

6.If you run above 2 steps in OS earlier than Windows XP, quit regedt32.exe and run regedit.exe.

7.Also in the HKEY_LOCAL_MACHINE\SYSTEM\MountedDevices registry branch selected, in the right pane, find and locate a registry value which represents the troubled USB or FireWire drive. The registry key should have the name that resembles the format of \DosDevice\X: where X can be any alphabet letter which corresponding to your physical system drive letter.

Here?s a guidelines that you can follow to quickly determine which registry key is linked to your conflicted drive letter:
Exclude \DosDevice\A: and \DosDevice\B: which normally reserved for floppy disk drives.
Exclude \DosDevice\C: which normally is the system root drive.
If you have more than one fixed hard disk drives, then any drive letters that are using by them is not possible linked again, UNLESS the additional hard disk drive is added AFTER you first use the USB or FireWire device that now unable to show.
Same case with CD-ROM or DVD-ROM optical drive as above reasoning.
If you have inserted and mounted a lot of thumbdrives, USB flask drive, or external hard disks before, you will likely still see a lot of remaining registry values that you won?t know which is which. In this case, double click on each remaining registry key values to view its binary data. Inside the binary data, there will be trace of the name of the device that this registry key represents.

With this information, search for a registry value that contains name of your USB or FireWire drive brand and model that having problem showing up in Explorer.

8.Once the correct registry value is determined (for example, \DosDevices\F:), right click on the registry value name, and the select Rename.

9.Change the drive letter (example F) to another unused drive letter that hasn?t been used by another other drives, then press Enter.

10.Now insert and plug in the USB or FireWire device into the port again (if it?s already inserted, take it out and re-insert again). The drive letter for the USB and FireWire should now appear and you can use the drive normally and properly again.

11.For OS earlier than Windows XP which you have previously change the permissions for the registry key, quit Regedit.exe and start Regedt32.exe, and change the permissions back to the previous setting for Administrators (which should be Read Only).
It?s also possible to simply delete the devices registry keys instead of renaming it. Deletion is helpful is users really can?t find the the registry value for the drive letter that is having problems. But make sure that you do a backup for the registry branch by exporting MountedDevices key, as mistakes may cause your system to be unbootable. Then delete all possible USB drives, FireWire drives and external drives which have drive letter temporarily only when inserted in the system, and DO NOT delete any of the fixed hard disk drives or CD/DVD optical drives registry values.
Happy Computing.
Please give a thumbs up if you find this info useful. Thanks.

Please post back if you have any more problems or questions.

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Have you actually tried reading all this gobbledygook?

by OldER Mycroft In reply to Delete Usb Drive Letter v ...

If so, perhaps you could explain all the bits I don't understand.

Erm, starting with the first sentence.

It reads like the product of Babelfish.

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It reads clear to me,

Sometimes you have to talk people through a problem that they do not understand, if you make it complicated they will not understand where you are coming from. But it depends on the person though. Read it how you will, the outcome is still the same.

Please post back if you have any more problems or questions.

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