USB not recognizing devices

I am having a fairly new problem with the USB on my Dell Dimension 4600 not
recognizing many USB devices when attached. This was somewhat of a problem
before but has gotten worse recently since reinstalling Vista Home Premium.
The devices such as a fingerprint reader which has always worked is 'not
recognized' some of the time when plugged in. A Lexar CF reader that has
worked on this computer in the past and works fine on other machines now,
gets the message that it is not recognized.It does'nt matter which USB input
it is attached to. According to the Lexar site no drivers are needed for
Vista.

Any suggestions?

Thanks

Open Device Manager and look for any changes to the Universal Serial Bus
controllers.
Scan for hardware changes, try uninstalling the ports and restart the system
and try connecting back the device to see if it will work.

You might also want to check the Event Viewer for any possible error
messages that might give a clue.
--
Best regards,
Andre Da Costa
http://adacosta.spaces.live.com

"Paul Schumacher" <> wrote in message
news:...
> I am having a fairly new problem with the USB on my Dell Dimension 4600
> not
> recognizing many USB devices when attached. This was somewhat of a problem
> before but has gotten worse recently since reinstalling Vista Home
> Premium.
> The devices such as a fingerprint reader which has always worked is 'not
> recognized' some of the time when plugged in. A Lexar CF reader that has
> worked on this computer in the past and works fine on other machines now,
> gets the message that it is not recognized.It does'nt matter which USB
> input
> it is attached to. According to the Lexar site no drivers are needed for
> Vista.
>
> Any suggestions?
>
> Thanks