USB flashdrive not recognised

  • Thread starter Thread starter laurence withau
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laurence withau

I have a laptop running Windows XP, a pc running Windows 7, and a USB
flashdrive which works in the laptop. It worked at first in the pc, where I
used it to back up files. Butt now I get an error message saying that Windows
does not recognise the device. What can I do? Any advice would be appreciated.
 
laurence said:
I have a laptop running Windows XP, a pc running Windows 7, and a USB
flashdrive which works in the laptop. It worked at first in the pc, where I
used it to back up files. Butt now I get an error message saying that Windows
does not recognise the device. What can I do? Any advice would be appreciated.
Click to expand...

The first thing you do, with any storage device having serious problems,
is make a backup. A sector-by-sector backup for example, doesn't care
what state the file system is in. Even if the contents are not recognized,
you can try copying it.

http://www.chrysocome.net/dd

That tool runs in a Command Prompt window, and you need to understand how
it works, to safely make a backup copy of the flash. In this case, I'm
displaying the entry for my 8GB USB flash. 8,019,509,248 bytes is the
total device size, while the FAT32 partition on it, takes 8,013,233,152 bytes.

dd --list

\\?\Device\Harddisk3\Partition0 <----- represents the whole stick
link to \\?\Device\Harddisk3\DR15
Removable media other than floppy. Block size = 512
size is 8019509248 bytes

\\?\Device\Harddisk3\Partition1 <----- my FAT32 partition
link to \\?\Device\Harddisk3\DP(1)0-0+10
Removable media other than floppy. Block size = 512
size is 8013233152 bytes

Next, I need some space on my hard drive, to store an image of the USB flash.
Since my USB flash is 8GB in size, I need an 8GB space on an NTFS partition
on my hard drive (FAT32 has a 4GB file size limit). Say there is 8GB of space
on my C: drive and the C: drive has an NTFS file system on it.

262144*30592 = 8,019,509,248 , so block size times count will copy it entirely.

dd if=\\?\Device\Harddisk3\Partition0 of=C:\myflash.dd bs=262144 count=30592

You adjust the block size (bs) and count parameter sizes, to suit the size
of USB flash you're copying. I keep the block size at a quarter megabyte or
smaller.

By reversing the order of the parameters here, if you needed to copy the backup
image back to the USB flash, you can do it later. This would copy all the
data back, if one of your recovery experiments fails (like say the TestDisk program
made a mess of things). But it is important to have a backup, as it may be the only
thing left when you're finished.

dd if=C:\myflash.dd of=\\?\Device\Harddisk3\Partition0 bs=262144 count=30592

*******

If the flash drive is completely inaccessible (no response at all), the
only way to get the files back is via a data recovery company. That can happen
if the USB connector has a broken wire, or the controller inside the flash stick
has been damaged by static electricity. The flash chip itself (separate from the
controller) may still be accessible at the data recovery company.

*******

Once you have a backup copy of the USB flash, then you can experiment with
other tools. Try TestDisk for example, and see if it can find a file system.

http://www.cgsecurity.org/wiki/TestDisk

http://www.cgsecurity.org/wiki/TestDisk_Step_By_Step

Don't do a save in that tool, unless you're convinced it has
really found your file system. You can press the control key and C
(control-C) if you need to quit the program, and no quit option is
offered.

If TestDisk cannot make any sense out of the drive contents, then you
can try a scavenger program, to find any files and make a copy of them.
These are examples of two free tools. You need sufficient free disk
space on your hard drive, for tools like these to store the broken
files from the flash stick. There is no guarantee that the file
names or file sizes will be the correct size or contents. Using
a scavenger can take days of cleanup later, to discover whether
anything of value was saved. These tools can never be perfect.

http://www.cgsecurity.org/wiki/PhotoRec

http://www.pricelesswarehome.org/WoundedMoon/win32/driverescue19d.html

All of the above are free tools. There is an endless stream of programs
for $39.95, that will attempt to recover your files for you. Or, the
services of a data recovery company can cost you hundreds of dollars,
depending on the effort required to recover the data. Since a USB
flash doesn't need clean room conditions, it should be easier to
attempt recovery on it than with a real hard drive. They need to hook
up to the flash storage chip directly, to see if there is still anything
inside. In this picture, the flash chip is item #4.

http://upload.wikimedia.org/wikipedia/commons/e/e2/Usbkey_internals.jpg

HTH,
Paul
 
Reset the BIOS ESCD data on the PC.

If there is no option in the CMOS setup to do this, take the battery out for
a few mins.
 
thanks for the advice. My problem is not with recovering files from the
flashdrive, it's with getting the flashdrive to work, in other words getting
the pc to recognise it. I'm worried, too, that it may not recognise a new
flashdrive if I buy one. According to Device Manager the error code is code
43, but that doesn't tell me much. I've tried the troubleshooting wizard and
uninstalled the USB and then restarted the computer, but to no avail.There
shouldn't be this problem with a new operating system such as Windows 7, and
it's annoying that nothing seems to resolve it.
 
Thanks for the advice, but it's too technical for me, and I wouldn't know
where to start, but thanks anyway.
 
message I have a laptop running Windows XP, a pc running Windows 7, and a USB
flashdrive which works in the laptop. It worked at first in the pc, where I
used it to back up files. Butt now I get an error message saying that
Windows
does not recognise the device. What can I do? Any advice would be
appreciated.
--
laurence withau

==============================================================

Try this;

Shutdown your computer. Pull the power lead out of the computer. Press the
power button on the computer. This makes sure there is no power still
running through the motherboard via the capacitors which continue to hold
power for some time. Put the power plug back into the computer and turn it
on. Try your USB devices again.
 
laurence said:
thanks for the advice. My problem is not with recovering files from the
flashdrive, it's with getting the flashdrive to work, in other words getting
the pc to recognise it. I'm worried, too, that it may not recognise a new
flashdrive if I buy one. According to Device Manager the error code is code
43, but that doesn't tell me much. I've tried the troubleshooting wizard and
uninstalled the USB and then restarted the computer, but to no avail.There
shouldn't be this problem with a new operating system such as Windows 7, and
it's annoying that nothing seems to resolve it.
Click to expand...

Sorry, I got carried away. I should have read your post more carefully.

When you plug a USB device into a computer, and the USB device has a
serial number, the computer may record certain things about it in the
registry. As a result, plugging it in later, may give the same bad response
as before. Windows consults the registry, and whatever is wrong, could
be because of something recorded in the registry.

If you wanted to clean out all memory of previous USB devices, they have
a procedure here. Take note of their comment about "USB keyboard". Sometimes,
on a desktop computer, you may lose the ability to use a USB keyboard, until
a procedure like that is completed. A PS/2 keyboard should work as a temporary
workaround, as long as the computer still has a PS/2 port.

http://www.usbman.com/Guides/Cleanup Device Manager Safe Mode.htm

The explanation for code 43 is here.

http://support.microsoft.com/servicedesks/webcasts/wc091802/devicemgrerrcodes.htm?gssnb=1

"(Code 43) Windows has stopped this device because it has reported problems.

One of the drivers controlling the device notified the operating system
that the device failed in some manner."

That implies the device connected, endpoints were formed, but something the driver
read from the stick upset it. Or, the connection dropped some time after
it was working.

The file c:/windows/setupapi.log may have an entry in it for your USB flash
device. Check the end of the file, to see the latest log entries as to
what is happening. Maybe there will be some hint there as to what is
wrong.

If you want to see the configuration information coming from the USB flash,
run this program, and watch its response when the USB flash is plugged in.
Click on the port the USB flash is plugged into, and you should be able
to see the configuration data. Seeing that data, proves that some level
of communications with the device is working.

*******
ftp://ftp.efo.ru/pub/ftdichip/Utilities/UVCView.x86.exe
http://www.users.on.net/~fzabkar/USB_IDs/UVCView.x86.exe

File size is 167,232 bytes.
MD5sum is 93244d84d79314898e62d21cecc4ca5e

This is a picture of what the UVCView info looks like.

http://www.die.de/blog/content/binary/usbview.png

Some information on the parameters seen in UVCView.

http://www.beyondlogic.org/usbnutshell/usb5.htm
*******

Another good page to consult, is the page of tips by Uwe Sieber.

http://www.uwe-sieber.de/usbtrouble_e.html

Paul
 
thanks again foir the advice> In 'search programs and files' I typed in
'c:/windows/setupapi.log'
but nothing came up. I tried the links you gave me, including to USB man,
but it was all too scary, and I was afraid of messing up.Perhaps I should
just buy another memory stick.--
laurence withau
 
thanks for the advice. I did as you suggested but it didn't work. Thanks
anyway.
 
laurence said:
thanks again foir the advice> In 'search programs and files' I typed in
'c:/windows/setupapi.log'
but nothing came up. I tried the links you gave me, including to USB man,
but it was all too scary, and I was afraid of messing up.Perhaps I should
just buy another memory stick.--
laurence withau
Click to expand...

You could just search your C: drive in the search box, and enter

setupapi.log

as the thing to search for. The search thing should be able to find it.

Paul
 
If anyone has the same problem, it may help if they do what I eventually did,
by trial and error, which was to insert the USB stick not into the front
ports but into the more inaccessible ones at the back of the box. It works
now, but before removing it for any reason I'm going to try to find out
whether I should use the 'safely remove hardware and devices' feature.
 
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