USB stick works with exFat but not with NTFS when full

I've just observed a very strange behavior. So I'm curious if anyone can explain this?

I bought these cheap chinese USB sticks on amazon (x10 for $40 or something like this.) They originally came pre-formatted as FAT32.

So I was trying to transfer several large files today and they didn't work with FAT32 (one was over 4GB in size.) So I formatted one of those USB sticks as NTFS and copied all the files there. (I did this on a Win10 desktop.)

But then the destination Win10 desktop refused to see that USB stick no matter how many times I tried to plug it in, wiggle it, etc. Even "Disk Management" did not see it.

Here's how the disk looked like on the source Win10:




Then I decided to try another file system, exFat, and to my surprise the same USB stick with the same data was recognized on both computers without an issue:

Okay, a couple of things here. The initial issue with files over 4GB makes perfect sense - you cannot write files larger than 4GB to a FAT32 partition. However, as soon as I hear "cheap Chinese USB stick" I worry about "fake" USB sticks. Problems with fake memory sticks can be seen in several different ways, depending upon exactly what has been done with the memory stick.

I would strongly suggest running a utility such as h2testw to test your memory sticks. See the article below for a description of this issue and links to utilities to test your USB sticks.

An example of a symptom you might see might be a flash drive that reports itself as 16GB in size, but is really only 4GB. You can try copying more than 4GB to it and it may report no errors but close inspection would show that when the drive is full it just starts overwriting existing data causing data loss.


5 Tools to Test and Detect Fake or Counterfeit USB Flash Drives • Raymond.CC

Again, there are several utilities - I like h2testw for it's simplicity.

NTFS and exFAT are very different file systems, exFAT being simpler. They use different portions of the disk in different ways. Likely the disk is in some way bad. With a cheap Chinese USB drive that is hardly surprising. I suspect that with NTFS something critical is using a bad portion of the disk, while with exFAT it is being used for data. Likely some of the files are corrupt, or you may find that most of the files are non recoverable. I wouldn't trust it for any purpose.

Fake drives are common with sellers in the orient. These are drives that have been modified to show a much larger capacity than actually exists. The packaging of such drives is often very good. In some cases drives have failed manufacturers tests and are are scheduled for destruction but dishonest employees have sold them to the suppliers of fake drives.

Thanks guys for all your replies. Couple observations and answers to your points.

@Compumind: I did not run it on a Mac. It was done only between two Win10 desktops. Both with the latest updates (versions.)
@hsehestedt and @Compumind: thanks for the tools. I'll try them tomorrow.

What's odd, guys, is that I was able to copy the entire 14.6 GB folder using the exFAT partition on that same USB stick and the files worked on the destination machine. (It was an Adobe installer, 3 .iso files, so I'm guessing that it wouldn't run if the file was half-baked.)

Also another interesting observation. Since I had about x10 of those USB sticks, I tried the exact same thing with another stick of the same capacity. And it repeated one-to-one. Again, steps are as follows:

Format it as NTFS. The stick gets recognized empty on both desktops. Then copy 14.6GB onto it from one PC, safely remove it, plug it into USB-3 port on the second PC and it just doesn't see it at all. Then format it with NTFS and the second PC again starts seeing it when empty. I can then repeat the same steps with another USB stick from the same batch.

(PCs are: the first one is my own build -- about a year old, gaming rig. No issues with USB ports. And PC 2 that refused to read that stick is Dell OptiPlex 3070 Micro, purchased from genuine Dell website.)

So I was about to throw out that USB stick myself, until I noticed this strange behavior (that I described above.) So then I decided to try another file system, which was available in the Win10 "format" menu, i.e. exFAT, and it worked! I was able to copy the entire 14.6 GB folder.

So the reason I'm posting this is not because I'm trying to save these cheap USB drives, I'm just genuinely curious what the heck had they done with them?

@Compumind: and about your question about trying it with "the same procedure with a name brand USB stick" -- I'm throwing it back at you -- what's the name brand? They're all made in China now. I don't know who to trust anymore.

using NTFS, does it work if you put a smaller file in it?
also I would try to reboot (not shut down, reboot) the 2nd pc after plugging in and seeing it empty, I had many weird behaviours with USB and NTFS

HTH.

Hi folks

@ahmd

What's up with all this aggro with "Cheap Chinese products" -- actually most of those probably don't come from China anyway but usually from cheaper sources e.g Vietnam, Indonesia etc.

I've never had a problem with these USB sticks .

If you want to format ntfs -- either boot up a linux live distro , plug the usb stick in and then as sudo type mkfs.ntfs /dev/sdx -f where /dev/sdx is the dev nr of the usb stick (ensure you have ntfs-3g package installed) or does the windows cmdline work --diskpart, clean, etc etc.

Cheers
jimbo

Nothing strange at all, Different file systems take a different space on a 16 GB drive.
You are trying to store 14.6 GB on to it, which is too close for comfort. You got to leave some room for managerial/file system tasks.