I have a USB card reader that I use to swap files between my desktop PC and a laptop- it's a Kodak 6-in-1 card reader and I use a CF 64 MB card.

For some reason when I try to unmount the card it always says "device is busy". If I try to force the unmount it tells me only root can do that, and as root I get device is busy.

I have the following in my /etc/fstab:

/dev/sda1 /mnt/card auto noauto,rw,users 0 0

Also after mounting and unmounting the device I have the following processes which remain even after killing them

1682 ? 00:00:00 usb-storage-0
1683 ? 00:00:00 scsi_eh_0

I wouldn't mind except that files are not always being written to the card when i expect them to be.

Can someone tell me what I've done wrong?