Hi, I was wondering if anyone here knows anything about the USB system on Linux. I have a Concord Eye-Q digital camera which I KNOW works on Linux as a mass storage device (I have gotten pictures from it before). Usually I plug it in, mount it to the directory /mnt/camera and get my pictures, then type "umount /mnt/camera" and pull the plug. However, the second time I plugged the camera in and typed "mount /dev/sda1 /mnt/camera" I got the error message that /mnt/camera did not exist. Sure enough, it had been mysteriously deleted at some point. I recreated the directory and tried again, only to discover that /dev/sda and /dev/sda1 had now disappeared! As if that wasn't strange enough, I discovered that I could fix the problem by moving to a different usb port. But the second time I use each one, it deletes my /mnt/camera and /dev/sda1. Even rebooting doesn't get them back. Does anyone know how to help?

Update: I found some interesting output from /var/log/messages. But I'm not sure what it means:

Jun 22 12:51:29 localhost kernel: Info fld=0xa00 (nonstd), Current sd00:00: sense key Not Ready
Jun 22 12:51:29 localhost kernel: sda : block size assumed to be 512 bytes, disk size 1GB.
Jun 22 12:51:29 localhost kernel: /dev/scsi/host1/bus0/target0/lun0: I/O error: dev 08:00, sector 0
Jun 22 12:51:29 localhost kernel: I/O error: dev 08:00, sector 0
Jun 22 12:51:29 localhost kernel: I/O error: dev 08:00, sector 2097144
Jun 22 12:51:29 localhost kernel: I/O error: dev 08:00, sector 2097144
Jun 22 12:51:29 localhost kernel: I/O error: dev 08:00, sector 0
Jun 22 12:51:29 localhost kernel: I/O error: dev 08:00, sector 0
Jun 22 12:51:29 localhost kernel: ldm_validate_partition_table(): Disk read failed.
Jun 22 12:51:29 localhost kernel: I/O error: dev 08:00, sector 0