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General discussion

USB device not recognised

Dec 31, 2008 5:05AM PST

HP DV6108 - running XP

When I plug my external hard drive into the USB port up I get this error.

"USB device not recognized
One of the USB devices attached to this computer has malfunctioned and windows does not recognize it, for assistance in solving this problem, click this message"

When I click on that message it pulls up a list of USB ports

USB Root Hub
Unused Port
Unused Port
Unknown Device
Unused Port
Unused Port
Unused Port
Unused Port
Unused Port

I only have three USB ports on the laptop. The external hard drive works fine if I plug it into either port on the left side of the machine. The port will work fine for a wired optical mouse and I just tried my IPOD and it worked. I use this port also for checking coeds one my car with an OBDII to USB connector, and that doesn't work(and can only work with that COM port). I only got this external a month or so ago and think that it might have screwed something up. I tried to do a restore, but that didn't change anything.

When I go into the Device manager it lists these under the USB

Universal serial Bus Controler

Discussion is locked

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Dec 31, 2008 5:17AM PST

Sorry wrong section - I'll repost over in "laptop" - Mod please delete

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I linked it here so others can chime in.
Dec 31, 2008 5:39AM PST

Without losing the added details.

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(NT) Which one?
Dec 31, 2008 5:20AM PST
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Dec 31, 2008 5:27AM PST

DV6108nr Didn't realize there where other 6108's

It's a 1 TB external that has it's own power.

Will try that driver and update

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Let's hope its not this model.
Dec 31, 2008 5:30AM PST
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read that
Dec 31, 2008 5:39AM PST

I read the post you linked to, but It's just one USB port that doesn't work the other two work fine. The brand of my drive is Cavalry.

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Didn't work
Dec 31, 2008 5:36AM PST

Installed that and nothing changed

Other idea's

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Then try the old fix.
Dec 31, 2008 5:42AM PST

Place an USB 2.0 HUB inbetween the non working port and the drive.

If this works then it's the old USB issues that have come back to haunt you. I don't want to type in what they proves but the choices are:

1. Use a drive that works in that port.
2. Use the USB 2.0 Hub.
3. Replace the motherboard.

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Dec 31, 2008 5:58AM PST

I have a warranty from best buy on this laptop, should I bring it in to them and have them diagnosis the issue, if it's hardware then they will replace what's bad, of course I'll have to backup everything first, since this is the wife's laptop

I don't have a USB hub right now, but I will go pick one up.

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Dec 31, 2008 6:20AM PST

It's only USB 1.x on the port that didn't work. Not unheard of and I leave it to you to research that. I did the research on why so many ports being reported.

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Why not go with what works where it works?
Dec 31, 2008 6:21AM PST

I think you wrote it works in the left ports. Why not go with what works?

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reason why
Dec 31, 2008 6:36AM PST

The reason why I need that port, is my Car code reader uses Com4 only and that port is set up as com4. Also, I like it when everything works the way that it should.

Thanks for your help, I'll get the USB hub tonight and give that a try.

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It worked - so that's a bad thing?
Dec 31, 2008 1:04PM PST

ok - I purchased a CyberPower 4 Port USB hub. That worked. I connect to the port via the USB hub and it reads the drive. What does this mean, it's for sure a Motherboard issue?

something else. I was looking in the device manager and realized that I was missing the "PORTS (COM & LPT)". Searched around and figured out how to get them back. New problem, I need was using COM4 before to connect to my car - now that says "in use" when I try to reassign the COM#. What would cause this? What is using the COM's? Is there a way to find out?
Sorry for all the questions. Thanks

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Just a link.
Dec 31, 2008 2:27PM PST is fairly technical but gives you a peek under the USB hood. The test is what it is and only reveals there is an issue with the USB clock and/or jitter. There is nothing that we do besides leave the usb hub there or replace the board that holds the not so great USB port. In the case of laptops this runs 300 to more dollars.

You can see why I just leave USB hubs installed.

My USB to Serial adapter does that same thing. It's in the documentation how to press onwards and make the change anyway. One owner was hopeless and refused to click the OK button to change it anyway in spite of the demo where I showed it was OK.
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About thoes other ports.
Dec 31, 2008 5:55AM PST

Read page 42 of

"USB host interface with support for eight USB ports; four UHCI host controllers; one EHCI high-speed USB 2.0 Host controller"

That ONE EHCI USB Host controller could be the killer item here. Since you didn't lead off with the model number I spent my lookup time finding out I didn't know what laptop you have rather than checking to see if HP had put USB 1.1 ports on one side and USB 2.0 ports on the other.

Look into that.

But that handily DOCUMENTS why you see more than 3 USB ports.