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Windows 7: USB Unknown Device Errors

27 Jun 2009   #1

Windows 7 RC
USB Unknown Device Errors

Hi All, I'm new around here but I've just solved a problem that may help anyone else who has the same thing happen.

I got a new Dell Studio XPS 13 laptop a week or so back, loaded Windows 7 RC and everything worked fine after a bit of fettling here and there. On Tuesday or Wednesday I had a problem where the laptop locked up while using a Logitech USB Radio mouse. Thinking the mouse caused the lockup, I disconnected it and have been using the touch pad since and no lockups. So far so good. Then today I plugged in a set of Logitech USB headphones for Skype and I got an 'unknown device' error. I tried with other USB items, ADSL modem, memory stick, all had the same problem on both USB ports and nothing I did would solve the problem. Much googling and a search of this forum again came up with nothing I could use. I then had a flash of brilliance - I figured it must have been the mouse that started the problem when the laptop froze and somehow something was blocking the USB useage. I plugged in the mouse whereupon it loaded up the software and worked fine, and now everything else loads up and works OK too!

I can't explain it, I'm just a programmer and don't really understand computers but if it helps anyone else in the same frustrating situation, there it is.

My System SpecsSystem Spec

19 Aug 2009   #2

Windows 7 x32

Hi Guys

Have read through this post, I have similar problem though I'm more confused now.
I have 3 External HD and one Semi-External (backup unit HP). None of them works through USB ports (none of my 8 ports).
Not even the four Mem sticks I have tried works.

Windows 7 says unknown devices.
1. I have tried all ports.
2. I have tried on Vista and XP on other machines (no problems).
3. I have had these units working on this hardware before (in vista).
4. I have the latest of everything as it seems.. (i think).
5. I have reinstalled with them plugged in and not like 4 times..
6. I have tried several updates and even tried with old USB drivers..
7. I found a writing on a 4 step check and did that to (power management, uninstall, checking power etc.. )
8. tried different cables
9. ...

What the H...

My keyboard works (W-less).. My Camera works.. ? on all ports..

Any one have similar problems ?
This is driving me crazy ..

Best Regards
My System SpecsSystem Spec
08 Mar 2010   #3

windows xp

I Have the same probleme except that nothing works on the USB ! Even the web cam included in the Hp Pvillion DV9443, doesn't work ! It's listed has unknow device.
I got that problem after I done a clean install of Windows 7. I have now gone back to Vista, but I now have the same with Vista. It was working fine before I try to install Windows 7?

Any clues ?

My System SpecsSystem Spec


 USB Unknown Device Errors

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