Model : WD10EAVS HDD Fault : USB cable was accidentaly removed from port while hdd was connected. Problem : wd hardware found ,but no drive letter. Tried : New external case (same result),tried on Sata(undetected)

You can purchase another identical External Drive and swap the HDD inside it to recover your data or simply install the removed drive into a Desktop computer as a secondary drive to recover if the problem is actually the USB port.

Try unplugging the computer from power, and the drive usb cable for ten minutes, this solve some problem on usb devices.

I have had similiar issues using caddies there seems to be many connecting parts that can fail or become old and dirty failing to make contact with the hard drive you could remove the hard drive and check these contacts make sure they are clean and making contact

or

You could just remove the hard drive from the caddy and connect it directly inside your computer as a normal hard drive
or

You would have to remove the hard drive and use a usb sata ide kit

you will then have to connect it to your computer using a usb port

http://www.bing.com/images/search?q=SATA+Power+Splitter&qpvt=SATA+Power+Splitter&FORM=IGRE

Once connected to another computer to a usb port and power supply you should get a message found new hardware and it should install the drivers it should show on your computer or you might have to install it manually

click start click on computer to open you should see this drive

If you dont.

Click start control panel administrative tools computer management device manager scroll down universal serial bus controllers you could see a Yellow Question / Exclamation Mark? ! or a Red X

you will need to update/reinstall drivers

right click to reinstall drivers.

If you can see your usb drive but its not working

ports (com&lpt) right click update driver

Once you see this drive just click on it to open and copy all or any data you want and save it to another usb drive

or get one of these

http://www.ebay.com.au/itm/NEW-2-5-SATA-USB-2-0-external-HDD-enclosure-case-AU-/221010079433?pt=LH_DefaultDomain_15&hash=item33753a2ec9

NEW!2.5" SATA TO USB 2.0 external HDD enclosure case AU

Hope this helps.

Connect hardisk directly to computer without usb
go to start > run > cmd
type chkdsk /p enter

it will fix your problem

remove hardisk via safe remove
and connect via usb cable

Try to test your WD Ext HDD to a different computer and check if you will get the same problem.

If the same problem persist try to use a different cable for your WD Ext HDD.

If still fails kindly ask the store where you bought the WD Ext HDD on how to retrieve your files and have WD EXT HDD replaced?

If your WD Ext HDD works to a different computer then update the BIOS and Chipset of the computer where your WD Ext HDD connected previously.

Hope this helps.

disconnect your WD ext HDD. and reboot your computer. then connect again. if still not showing. go to device manager (right click my computer then properties -- click device manager). expand by clickin "Disk drives" category here it will show all the hard drives installed in your computer including your WD ext HDD . if you see yellow sign on your external drive right click and remove then go to Action menu click on Scan for hardware. it should detect and install the driver again. if still the same or maybe its not on the list of Disk drives.. try to change another USB cable .. i hope this will help

there is one possible way
1. remove hard drive from your laptop
2. plug your HDD into another laptop in anyway(usb or enclosure)
3. Make your HDD bootable with DOS mode
4. copy the new OS folder to your HDD
5. Put back your HDD to your old laptop then boot it with DOS
6. find the OS folder you copied, from there run setup your new OS.

One or more of the hints below will probably sort out most USB problems with most USB portable / external hard drives and OTHER devices (though not always)

A few things to check but assumes USB and Windows for other interfaces / operating systems (mac/ Linux) similar steps may be adapted to suit.

1. Ensure it is connected directly to the computer to a USB 2.0 port not a USB 1.0 port as this can have effects on performance and reliability

2. Use only the cables that came with it NOT one that fits that may have been lying around or is longer. Not all USB cables are equal even though they should be)

3. Do not connect through an external USB HUB unless that hub is USB 2.0 AND has its own power supply.

4. Use ONLY the power supply that came with it if it has an external power supply Don’t use any other unless you know it has both the same voltage and current rating e.g. 12V 500mA anything rated below that would not work properly.

5. Always use the same port for connecting your devices. Some devices do not like being switched about. If switched they may want to install software / drivers again. This can be especially true if you move a HUB to another port

6. For FLASH DRIVES you should ensure that the device is set for "quick removal" using the drive control panel properties or use the USB "Safely Remove Hardware" option. If you don’t do this there is a very strong chance that any files you transfer may not be there when you plug into another computer.
7. It is possible to remove drives from the enclosures in most cases and connect directly inside a PC to fully check it.
You should also do this to check the drives connections are not bad inside the enclosure.
　
8. If none of the above steps help look at updating the drivers from the manufacturers web site in the support section.

9. If you checked and fixed anything there and still have issues then check your hardware from CONTROL PANEL / SYSTEM / HARDWARE.
Any exclamation marks by hardware need fixing before you investigate any further
10. Ensure that you have set removable drives for "quick removal" or that you use the "Safely Remove Hardware" option often shown on the lower toolbar. It is possible that files my not be fully written to external devices before they are removed. This corrupts the file itself and even on occasion the drive.
SPECIAL NOTES
USB flash drives can fail for no apparent reason.
Sandisk Cruzers are especially bad for this.

USB hard drives should be treated with extreme care.
This is a real hard drive ! And knocks and bumps can quite literally kill them.

Note that if you hear a drive clicking or pinging this could be the worst thing you would hear.
Known as "The Click of Death"
Hope this gives you the information you need

Bob
Moderator

It would be very decent of you to consider the quality of our expert’s answers and judge them accordingly as you pass through FixYa.

Thank you

Hi,
It could be either because of loose connection or fluctuating current supply to HDD. So make sure there is no loose connection. For the second problem, connect both the USB pins for the cable, if provided with the HDD. Also try connecting the hdd to different USB ports as well as to different computers.
If nothing solves your issue, then the problem is internally in the HDD, you have to get it repaired.
Please come back and rate my solution if it turns to be helpful for you. Thnx

1st dismantle the hdd and change sata to usb adapter. Get cheap on ebay. Certainly, most wd makes hdd motherboard with usb straight away, but still worth to try. BUT, before all check if your pc usb is working, check with mouse or smth. If so, then try change cable. After cable try dismantle that hdd and change mentioned adapter. If none of these work, you then have a lesson, never western digital, seagate only1