USB device suddenly becomes "unknown device"

[Guest Pawel S.]

hi guys,

 

today something strange happened to my 4port usb hub. after

soft-rebooting my system i wondered why my external drives and mouse

didn't work (all connected to my usb hub).

at closer look i found out that an "unknown device" is plugged into my

machine which happened to be the usb hub.

 

of course i tried unplugging and replugging it to other usb ports but no

effects at all - stll unknown.

 

so i googled and found out that some people have experienced similar

problems and solved it by uninstalling all usb devices from the device

manager, deleting an "infcache"-file and rebooting. (and yes, i did "set

devmgr_show_nonpresent_devices=1" and did remove the nonpresent devices).

no effect. windows boots, installs and detects all usb devices but the

hub still remains unknown.

 

the odd thing about that: it's not a hardware failure. the usb hub works

perfectly in knoppix or in the BIOS setup (tried it with an usb-keyboard).

 

furthermore all other usb devices do work on my usb ports and the usb

hub works great on other machines.

 

system recovery and safe mode have also no effects.

 

i'm really puzzled. any ideas?

 

 

regards

pawel

 

PS: i've also tried several chords.

[Guest The Todal]

Re: USB device suddenly becomes "unknown device"

 

 

"Pawel S." <katzenstreu@gmx.net> wrote in message

news:6i9p5eFp8t37U1@mid.dfncis.de...

> hi guys,

>

> today something strange happened to my 4port usb hub. after soft-rebooting

> my system i wondered why my external drives and mouse didn't work (all

> connected to my usb hub).

> at closer look i found out that an "unknown device" is plugged into my

> machine which happened to be the usb hub.

>

> of course i tried unplugging and replugging it to other usb ports but no

> effects at all - stll unknown.

>

> so i googled and found out that some people have experienced similar

> problems and solved it by uninstalling all usb devices from the device

> manager, deleting an "infcache"-file and rebooting. (and yes, i did "set

> devmgr_show_nonpresent_devices=1" and did remove the nonpresent devices).

> no effect. windows boots, installs and detects all usb devices but the hub

> still remains unknown.

>

> the odd thing about that: it's not a hardware failure. the usb hub works

> perfectly in knoppix or in the BIOS setup (tried it with an usb-keyboard).

>

> furthermore all other usb devices do work on my usb ports and the usb hub

> works great on other machines.

>

> system recovery and safe mode have also no effects.

>

> i'm really puzzled. any ideas?

 

Try a different hub? I have a similar sort of problem with a USB2 cardbus

card on my notebook, which keeps showing as unidentified device and I have

come to the conclusion that it must have developed a fault.

[Guest Pawel S.]

Re: USB device suddenly becomes "unknown device"

 

 

> Try a different hub? I have a similar sort of problem with a USB2 cardbus

> card on my notebook, which keeps showing as unidentified device and I have

> come to the conclusion that it must have developed a fault.

 

.... how could it have developed a fault if it still runs perfectly on

the same machine but on a different OS.

 

this looks clearly like a software issue to me.