Why doesn't my card reader work?

May 3, 2007 11:10 PM

Why doesn't my computer recognize my USB flash card reader anymore? It makes a noise when I put it in and remove it, but it doesn't show up as a removable device and I can't seem to figure out how to access it (I'm on Windows XP).

The flash card works fine in my camera.

posted by borkingchikapa to computers & internet (10 comments total)

First thing to check, if you haven't, is the card and reader in all the USB ports on your computer. If it's a desktop there should be some on the back as well as the front, including some that a mouse and keyboard might be plugged into. If it fails to work there then try it on another computer to verify that it is your computer and not the flash card reader itself which could potentially fail, in which case replace the reader.

Sorry I don't have any XP specific advice for you to check if it's an OS failure instead of a hardware failure.
posted by 6550 at 11:38 PM on May 3, 2007

Try using an external hub.

USB 1.1 had a strange standard regarding power, where some devices wanted to draw half an amp and some only 100 milliamps. A slot could be rated to source half an amp or only 100 milliamps. During the handshake, a higher-power device would ask for permission to use half an amp, and if the slot said "no" then the device wouldn't come up.

I had an external sound module like that; it was USB 1.1 but I could only use it with USB 2 slots on my laptop because all the USB 1.1 slots were limited to 100 milliamps, and the sound module wanted half an amp.

An external hub solves the problem. It's got its own power brick and all its slots are high power. (An external hub without a brick would be useless, therefore.)
posted by Steven C. Den Beste at 11:53 PM on May 3, 2007

Some USB devices do not handle having their assigned drive letters shifting around - have you recently installed any other USB based external hard disks or CD-drives? Printers with built-in card-readers could grab existing drive letters as well..

You might want to try unplugging these kind of devices and then plugging in your card reader.
posted by your mildly obsessive average geek at 1:11 AM on May 4, 2007

My computer has this same problem intermittently ... with a combi USB card reader and external disk drive plugged into a PCMCIA USB2 card ... generally I remove the PCMCIA card and plug it in again and/or reboot the laptop (which may not be all that much help to you).

It seems that XP's USB stack is a pile of crap ... I have reinstalled the OS twice to gain a short reprieve from this problem and will do so again in a few weeks ... again this may not be much help.

So in a nutshell you are not alone,

You could look at http://www.usbman.com/WinME%20USB%20Guide.htm for additional information
posted by jannw at 1:34 AM on May 4, 2007

Also try connecting the device with a different USB cable. Sometimes the cables go bad.
posted by fuzz at 1:50 AM on May 4, 2007

Happened to me yesterday. I figured I'd shutdown the computer in case any process was hogging the port. It worked. Have you tried that yet?
posted by special-k at 6:04 AM on May 4, 2007

It seems that XP's USB stack is a pile of crap

Not really, it's just very dependent on the quality of the hardware.

Your best bet, as SCDB mentioned, is to try a powered hub. You can also go into the Device Manager to see if your card reader shows up as disabled - sometimes you can simply remove the device from Device Manager, have it rescan your computer, and pick up the device again.
posted by me & my monkey at 7:31 AM on May 4, 2007

To fix the drive letters moving around, the quickest way is to right click on my computer, manage.
Then in the left pane click disk managment
You'll see the eff-d up drive on the right with a little icon showing that there's a conflict. Right click on that drive in the top of the list and change the drive letter.
posted by ijoyner at 8:33 AM on May 4, 2007 [2 favorites]

ijoyner is right.
Change the drive letter. This should solve your problem
posted by winterhat at 8:56 AM on May 4, 2007

Thank you, ijoyner. I was just able to solve a long-standing problem with my camera connecting via usb.
posted by frykitty at 7:35 AM on May 5, 2007