USB stick inaccessible on the desktop

Q I am trying to get access to a USB memory stick. Grepping dmesg for USB results in the following

USB Universal Host Controller Interface driver v3.0
uhci_hcd 0000:00:1f.2: new USB bus registered,
assigned bus number 1hub 1-0:1.0: USB hub found

So it appears the USB system is recognised. However, I can't access the stick from the desktop. How do I mount the stick (without being arrested or ending up in casualty)?

A While dmesg shows information about your USB interface, any mention of the device itself is suspiciously absent. It's often easier to look at the system log for this sort of information. This is usually /var/log/messages or /var/log/current, depending on which system logger is in use (you don't mention which distro you use so it's impossible to say for sure). Run

tail -f /var/log/messages

as root, before you plug in the USB stick, then watch the output as the stick is recognised. You should see something like this

usb 7-5: new high speed USB device using ehci_hcd and address 16
usb 7-5: configuration #1 chosen from 1 choice
scsi14 : SCSI emulation for USB Mass Storage devices
usb-storage: device found at 16
usb-storage: waiting for device to settle before scanning
scsi 14:0:0:0: Direct-Access Generic USB Flash Disk PMAP PQ: 0 ANSI: 0 CCS
sd 14:0:0:0: [sde] 2007040 512-byte hardware sectors (1028 MB)
sd 14:0:0:0: [sde] Write Protect is offsd 14:0:0:0:
[sde] Mode Sense: 23 00 00 00
sd 14:0:0:0: [sde] Assuming drive cache: write through
sd 14:0:0:0: [sde] 2007040 512-byte hardware sectors
sd 14:0:0:0: [sde] Write Protect is offsd 14:0:0:0:
[sde] Mode Sense: 23 00 00 00
sd 14:0:0:0: [sde] Assuming drive cache: write through
sde: sde1
sd 14:0:0:0: [sde] Attached SCSI removable disk
sd 14:0:0:0: Attached scsi generic sg6 type 0
usb-storage: device scan complete
hald: mounted /dev/gigabyte on behalf of uid 1000

In this case, the device is recognised as /dev/sde with one partition, which is automounted. If you see no references to usb-storage, make sure the usb storage module is loaded by examining the output from lsmod:

sudo lsmod | grep storage

If the module isn't loaded, try loading it with sudo modprobe usb-storage and inserting the device again. If the usb-storage module is loaded, it's very unusual for a device to be unrecognised. Try it on a different computer: Flash memory has a limited lifetime for writes and the FAT table is often the first place to stop working on a FAT formatted device, which could result in this behaviour.

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