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Question

Usb working on 3.0 port but not on 2.0.

Mar 27, 2016 11:38AM PDT

I have an ADATA 8gb USB 3.0. In the start it worked well, but now i am facing a problem, it is working only when it is plugged in 3.0 port and when i connect it to usb 2.0 port the computer shows the error USB DEVICE NOT RECOGNIZED. and i am getting same error in 5-6 computers as i have checked it on a number of PCs. but when i connect some other usb 3.0 to my pc, on 3.0 or 2.0 port it is detected and works well.
how can i fix my ADATA usb? do i need to install the usb's default internal software/bootloader?

Discussion is locked

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Answer
So the problem is this stick itself,
Mar 27, 2016 12:49PM PDT

I probably just go and buy another one (maybe different brand). Internal software/bootloader...what are we talking about?

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Answer
There's a few possibilities
Mar 27, 2016 1:16PM PDT

USB 3.0 provides more power than 2.0 does, so I suppose it's possible that the 2.0 ports aren't providing enough power to it. However I doubt that given that it's just a thumb drive.

The other possibility has to do with the data channel. USB 2.0 only has one data channel pair of contacts, while USB 3.0 has two. Perhaps one of the 2.0 traces or contacts is damaged, dirty, or otherwise not connecting, but the second channel over 3.0 is working.

In either event the simple solution is to just spend $5 to replace it.