Counterfeit WD20EARS?

I recently bought this WD20EARS drive on eBay, and I wonder whether it might be a counterfeit.

The label says its a WD20EARS-42R6B0, but if I plug the serial number into the WD warranty check, it shows up as model number WDH1U10000PN rather than WD20EARS.  If I run the Windows Data LifeGuard Diagnostic, it gives a different serial number, which the WD warranty check shows as “INVALID SERIAL NUMBER”.  Looking harder at the label, the DCX number looks like it might be invalid in that some of the middle letters of the model number suffix (42R6B0) should perhaps be reflected in parts of the DCX number, as suggested at

What do you reckon?  Any help would be very much appreciated.



It could be, I would try calling WD directly.

The WDH1U10000 model number is a 1TB My Book Essential Edition 2.0:

AFAICS, the original drive in the enclosure would have been a 1TB Caviar Green.

The model number suffix (42R6B0) is not listed in the following document, but the “42” does look like it may be an OEM identifier, or it may refer to WD’s external products.

In fact here is a “42” WD20EARS with an Apple logo:

Compare the warranty expiration date against the date on the label. Be aware that the warranty period may allow several months for on-the-shelf time. Also compare the label against the date codes on the chips. I can help you with this if you upload a photo.

BTW, I notice that there is a single period after the “MDL” above the barcode. AFAICT, a genuine drive should have a colon in that position.

Also, immediately above the model number are two lines:

“Additional jumper settings available at

That’s a grammatical error.

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Not to mention “US Partents” instead of Patents.
And largcapacitydrives missing the e in large.

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Thanks very much for all your replies.  I hadn’t spotted the errors on the label.  The spelling mistake “Partents” instead of “Patents” seems conclusive.

There’s another (less sinister) possibility.

WD may have made that drive as a WD20EARS, but failing specific post-manufacturing tests, they “Bin Sorted” it to be installed in an external enclosure, never intending to see the light of day on its own, and programmed the PROM’s and firmware appropriately.

The P/N you provided is actually the P/N of a 1TB external MyBook drive.  

I guess it’s possible someone’s enclosure broke, and they pulled the drive out and used it for another purpose and then sold it like that.

I don’t know if WD has the habit of releasing labels with printing defects or not.   If they were meant to be sealed inside another device, they may not have cared.