HOW TO TEST FOR FAKE USB DRIVE

Posted in 2007 

So you think you have been sold a fake USB drive AKA Pen Drive / Flash Drive / Memory Key.

Plenty of people are being fooled by dishonest sellers and manufacturers.

It's one thing to be sold the wrong size drive, but these "hacked" drives which appear on your computer to be the right size, actually corrupt your valuable data to make it look like it fits on a much smaller capacity memory chip.

Part of the clever cover up of this scam, is that the corrupted files transfer back off the drive at the correct size. So when you cant play or open some of your files, you think it's your software or even a virus. You need to do a proper binary level comparison of the original and transferred files to be able to tell.

The best way to check the true capacity of a USB drive is to read the part number off the memory chip & look it up on the web. But not many people are going to want to crack their drive open.

So here's another way for Windows XP users.

Fill it up with multiple Image files that you can check. Here's how...

First of all, transfer any files you need to keep off your USB Drive, then format it.
Start / My Computer.  Right mouse click on the USB Drive & choose Format.
This will wipe it totally clean. Make a note of what drive letter your USB Drive is and how big it is supposed to be.

You will need a bitmap (.bmp)  image file, simply because they are nice & large and take up lots of space. We will be viewing thumbnails of this image so you will want something squarish in shape, 2000 x 2000 pixels in size would be great. Don't worry if you don't have anything handy. You can just press the 'Print Scrn' button on your keyboard to take a snapshot of your Windows desktop - then open Start / All Programs / Accessories / Paint. In Paint select Edit / Paste then File / SaveAs. Name your file 'test'. By default it will save as a bitmap. Put this test.bmp file on your USB Drive.

Open up My Computer and double click on your USB Drive Icon so you can see the test.bmp file inside. From the menu up the top of the window, select View and change it to Thumbnails. You should be able to see a small image of test.bmp. This is important for later because you will be able to see straight away any corrupted files because they wont display their thumbnail image correctly or at all.

Now we need to fill our USB Drive up with lots of identical copies of test.bmp to see how many it can hold. To do this we will make a batch file. Open up Windows Notepad. Start / All Programs / Accessories / Notepad. Copy & Paste the following lines of code into notepad.

cls
@ECHO OFF
ECHO. ********************
ECHO. Fake USB Drive Check
ECHO. ********************
ECHO. Test File duplicator
ECHO. ********************
ECHO.
PAUSE
SET var=1
:LOOP
ECHO Creating file No."%var%"
set /a var=%var%+1
COPY z:\test.bmp z:\test"%var%".bmp
GOTO LOOP


In the second to last line "COPY z:\test.bmp z:\test"%var%".bmp". Replace the Z's with the drive letter of your USB Drive. Be careful to put in the right letter, you don't want to fill up the wrong drive.

Save the file as TEST.BAT to your desktop.

With you USB Drive open, double click on the TEST.BAT file you made. Your USB Drive will slowly fill up with copies of test.bmp 
For simplicity the batch file is a quick & dirty loop, when your USB drive is full you will see it start counting very fast and display  "there is not enough space on the disk" to stop this loop, just close the window.  With a hacked USB Drive, this file copy process will speed up and slow down as the Drive works out how to hide your data.

When you have finished, give windows a few moments to update the window and build the thumbnails.

Now you can scroll down the USB Drive window. If you see lots of images that all look the same - Great - your USB drive is fine. However, if any of the images look different  i.e. have any funny lines through them or large grey blocks that the first file doesn't have. Or if some of the file names are garbled, or some of the files remain icons and wont change to thumbnails & wont open when you click on them. Then you probably have corrupted data.

If that's the case, the next thing you can check is the sum of all the good files to see what the actual capacity of the drive is. Hold down the 'Ctrl' key and select all of the thumbnails that look OK. Do not include any bad images. When you have them all selected, right mouse click and choose Properties.  The properties box will show you the combined size of the selected files. 1000 Mb equals 1 Gb.

So if you bought a 8 Gb USB Drive like me, but the total size of all the good images is about 1950 Mb, then what you have is a hacked 2 Gb Drive.

Get a refund!