User Feedback :: /dev/sda1 is not a valid block device

I'm gonna use DSL to rescue a system and need to backup important files to a USB device, namely a digital camera, as I have no other type of device.
Anyhow, I've booted into DSL, I am su:ed to root, and I plug in the running camera.
Dmesg says that it recognises that a camera is plugged in like:
"New usb devie found, assigned to address 5.
USB device is not claimed by any active driver" (with a bit of extra non-human-readable info.)
When running lsmod, I have all possible usb modules.
Meanwhile, in /proc/bus/usb  there's the files 'devices' and 'drivers', and the folders 001 and 002.
In folder 001, the files change when I reconnect the camera to match the address that dmesg gave, like 005 -> address 5
So according to every piece of documentation I've read, I've just to run:
mount -t vfat /dev/sda1 /mnt/usbdrive
to mount it.
However, when I do, it gives me the error:
mount: /dev/sda1 is not a valid block device

I get the same error when I try sda2-sda11 and sdb1-sdb11.

fstab assumes /dev/sda1, so the mount.app can't mount it either.
The mount button is blank and non-clickable.

It's an HP digital camera.
I dunno if that makes any difference, but I've had the experience that they make up things of their own a bit...

I've vaguely wondered about this in the past and would love to know if anyone has used this technique successfully.

And not just on Damn Small although that would be a bonus

Also, look at your /etc/fstab.
I believe that DSL picks up all partitions,  etc. when it boots, and will show them there. You should have the camera plugged in and turned on when you first boot DSL, and see if it gets picked up in the /etc/fstab file.
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Here' mine on a Toshiba Laptop, one partition on the hard drive, and a Dell USB memory stick, 64 MB  plugged in as my restore device.
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none       /proc       proc   defaults            0 0
none       /dev/pts    devpts mode=0622           0 0
/dev/fd0   /mnt/auto/floppy auto   user,noauto,exec,umask=000    0 0
/dev/cdrom /mnt/auto/cdrom  auto   user,noauto,exec,ro 0 0
/dev/sda1  /mnt/usbdrive  auto  user,noauto,exec,umask=000  0 0
/dev/hda1 /mnt/hda1  auto   noauto,user,exec 0 0
----
As you can see, it picked up the usb drive at /dev/sda1
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Just a thought, hope it helps. btw, that "not a valid block device" also will turn up if you try and mount a floppy, and you forget to put the floppy in the drive!
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