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I have a small USB 3.0 usb flash drive and have put some data on it with my computer (USB 2.0). Everything worked fine.

When trying to give that data to a friend, it wasn't recognized. After the fifth try Windows self-installed some drivers. But the connections wasn't stable, I had to plug out and plug in the flash drive several times.

Then on a USB 2.0 hub I had to plug in the flash drive in a special position and if it was slightly moved, it was disconnected.

So my question is: Is that specific to my flash drive so that I shall use my warranty or is that specific to USB 3.0? Is there a small adapter available (USB 3 socket, USB 2 plug), so that the device will work on every port?

(I never had that kind of problem before with any USB 2.0/1.1 device)

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migrated from Jan 12 '13 at 20:52

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USB 3 is supposed to be 100 % retrocompatible with USB 2. I don't think there's such a thing as a proper USB 2 port that won't take USB 3 devices. The idea that it works in a certain position but won't if you move it tells me it's probably a physical problem, and has nothing to do with compatibility.

Your first step will be to try to determine what piece exactly is the problem.

Possible reasons:

  • The USB hub is not sufficiently powered, or for some reason has trouble with USB 3 devices, or even though it's plugged into a USB 2 port, the splitting makes each port work like a USB 1 port. Try putting it directly in the PC's USB port.

  • Your friend's USB ports are actually USB 1, be it because of the port itself or the hub, and compatibility of USB 3 devices with USB 1 ports isn't guaranteed.

  • The USB port on the PC has an issue. Try changing ports.

  • Make sure the problem is not with your friend's computer only.

  • The USB cable or one of its connectors on either side has an issue, if it's similar to an external hard drive and you plug it using a cable.

  • Your drive's USB connector is faulty and has bad contacts.

  • Your flash storage device itself has an issue (unlikely IMO, because in that case the problem wouldn't feel so specific).

If the problem is your friend's PC, I can't guarantee that you'll be able to solve it easily, but if that's the case, at least you'll know your device is not the problem.

If you determine the problem is one of the two last list items, then yes, it would be appropriate to contact the manufacturer or retailer. If your drive uses a cable, you could also try to just find a replacement cable.

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I tried a USB 3 hard drive on my computer and it worked well with the case ports and with an additional USB cable. – u_Ltd. Jan 13 '13 at 19:40
The USB 3 flash disk did NOT work with the case ports, but did work with the additional USB cable. This additional cable (USB 1 BTW) could be plugged in everywhere and the flash disk worked. So the answer is: 1. My drive's USB connector is of poor quality 2. The USB ports on many PCs have bad contacts (because of heavy use in my case?) – u_Ltd. Jan 13 '13 at 19:53
I have bended the connector slightly inwards and got better results on one port, but other ports still don't work. I will try to delete the data and take the warranty. – u_Ltd. Jan 13 '13 at 19:54
@u_Ltd. Yeah, I'd suggest that. If the USB ports on your computer have issues, it's probably not so complicated to change them - those on the front, that is. Those in the back are most probably attached to the motherboard, and it'd take pretty professional work to change them, assuming it's even possible. :p – Ariane Jan 13 '13 at 20:52
FYI: Today I went to the shop where I buyed the flash drive and got a new one without problems. It works well on all ports I tried so far! @Ariane: That's right. And when you are using a mobile computer, you cann't really do anything about your ports. – u_Ltd. Jan 26 '13 at 12:12

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