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February 2017
Fake Flash

Your flash memory might not be as big as you thought!

Fake USB devices and SD flash cards like the SD and Micro SD cards for your smart phone, camera or tablet are more common than you might think. Counterfeiters have flooded the market with fake capacity flash drives that are convincing look-alikes for many of the popular brand name flash drives. The cases look almost identical and they are very often sold in convincing brand-name labeled packaging.

Just say NO to Fake flash
It may say 64, 128 or even 512 GB on the label and report that to the operating system when you insert it into your device but only be able to store 2 or 4 GB of data. It will even work at low usage levels but once you exceed the “true” capacity of the drive newly written data will be lost – written to the “bit bucket”.

It may look like the data is still there and you can even copy the files back to your system. But when you attempt to open the corrupt files you discover that your pictures, videos, music or documents are irretrievably gone. This could lead to massive data loss on top of the money you lost buying a 4GB drive for the price of a 128GB drive.

How is this possible?
The fake product is usually made from a poor quality or defective smaller flash memory chip. Often a 2nd rate 'reject' memory chip that should have gone to the furnace but was “obtained” from the trash can in back of the factory! The controller has been re-programmed to falsely report its capacity as say 128GB to Windows, iOS and other systems.

Are all the sellers on eBay and Amazon selling fake flash?
Oh no, there are many honest sellers online. Sometimes honest sellers are selling fake flash because they themselves have been duped. Even major retailers are not immune to this problem. To be safe you should test your drive before trusting it with your valuable data.

My 128GB drive only shows 120GB free. Is it a fake?
Not necessarily, it is normal, in fact necessary for a flash drive to reserve some space to support internal controller overhead. Some drivers reserve space for security, encryption, other software and drivers or DRM, (Digital Rights Management). Frequently this could take up 5-10% of the drives capacity leaving 90-95% for your data.

This is legal. It is an accepted industry practice to state a flash drive's capacity based on physical memory, not available memory.

How can I tell if my flash drive is a fake?
There is only one way to be sure and that is to test it. The basic format and surface scan, (CHKDSK for you old school types) will not detect the fakes. The only way to test your flash drive is by writing data, a lot of data, to the drive and then verifying that the data is still readable. You could do this yourself manually by copying a bunch of files, say music files to the drive and then playing them back to see if any of them fail to play. But this could take all day on some of the larger drives. I recommend testing to at least half the stated capacity of the drive. I would also recommend that you do a quick format of the drive first.

There are several testing programs that you can use. The best one is h2testw. It is not a virus and it will not damage your drive. Although the fake flash sellers would have you believe that. It was written by Harald Bogeholz and released by the German technology magazine c’t specifically to test for underperforming flash drives. The publisher of this magazine, Heise has it available for free on their website at You can download it from a number of other sites too but be wary of sites that bundle it with downloaders, toolbars and other “crapware”.

H2testw downloads as a zip file that unpacks into h2testw.exe and a couple of readme files. It does not need to be installed or require any special privileges. Just double click to run. Operationally it writes files of test data to the destination you specify and then reads it back to verify the data. Make sure you do the verify part. This can take a long time. You may want to set it up and let it run over night.

Not a "Good Deal"!

What if I have a Mac or other non-Windows device?
UNIX and Mac machines are just as susceptible to this scourge as their Microsoft brethren. Use the program F3, (Fight Flash Fraud or Fight Fake Flash) written by Michel Machado of Digirati You can download F3 from GitHub at It works in much the same manner as h2testw by writing data to the drive and then reading it back and verifying the data.

Other apps for testing flash devices on Android or iOS devices are available from Google Play and the iTunes store.

Can the fake flash be fixed?
With the proper “tools”, (special software) you could re-program the drive back to its true capacity and it will work as a lower capacity. But now you are paying for a high capacity drive and getting a low capacity drive. Not what I would call a good deal.

I do have a fake flash. What should I do?
Demand a refund right away! Amazon and eBay have buyer protection programs and most of the time the fake flash seller will quickly refund your money so as to stay out of trouble with Amazon, eBay and the authorities. Also they need to avoid negative feedback that would prevent others from buying and stop their illicit gravy train from continuing to bring in the money.

Once you get your money back complain to the online authority! Amazon, eBay, PayPal and most credit card companies have whole divisions devoted to online fraud prevention. But they can only take action once a pattern of deception can be found. Notify them as soon as possible and give the seller a negative review. Remember these are not simply defects. They are intentionally altered devices designed to screw you out of your hard earned money. Fight back!

For more information see the excellent article All About Fake Flash Drives 2013 on eBay at

And remember always back it up!

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