USB memory stick can't be unmounted

[UgoDeschamps]

also, the device name sometimes changes from /dev/sde1 to /dev/sdf1. I haven't figured out on what occasions exactly it does this. The change seemingly occurs at random times.

This is an actual problem, this meen's that the usb device, got "unpluged" or stoped responding, and got "replugged", this is where the SDE1 got detected at first (bootup usualy) then when this gets unplugged and plugged back in, it need to alocate a new SD. this is where the SDF1 comes into play.
I Dont have a very big knowledge over this, but I would suggest that hotplug could be faulty if this occur at random occasions, AND mabye a faulty USB port... Also, if you using a LAPTOP this could also be an issue if you run under the battery, aspi "mabye" turns some "useless" devices off for battery saving... Again I must advise you that these are all hypotetic since Im not an expert, but it should give you / other idea on the actual problem.

Also, I can't get filenames longer than 8 char's on the drive with linux. It is formatted with FAT. How can I fix that?

I am not a 100% sure about this, slap me if I'm wrong,... FAT is a very old filesystem and mabye it only support 8char fileName + 3 char extention... I remember having a computer like this, but it's been to long I havent used FAT... sorry if that confused you. Here an option tho. FAT isnt that of a good filesystem. FAT32 is way better, and if you dont need windows support, go for something like reifers or etx3 they both integrate journalizing (like NTFS does) and is fragmentation free! which is the GREATEST advantage over any other filesystem... In order to do that, you WILL have to format the drive to another filesystem. If you need more information on that just ask.

Hope this helps

[shoffsta]

Thanks for the help. The drive works now.
The problem I think was, that I made a mistake when I formatted the drive.
After I formatted the drive on another windows computer, I could unmount and it works perfectly.

[hitu]

hitu@kinky:~ $ umount /mnt/usbflash/
umount: /mnt/usbflash: device is busy
umount: /mnt/usbflash: device is busy
hitu@kinky:~ $ su
Password:
root@kinky:/home/hitu # lsof | grep usbflash
famd       3861       root  221r   DIR        8,1    16384          1 /mnt/usbfl ash
famd       3861       root  225r   DIR        8,1     4096     131925 /mnt/usbflash/system
famd       3861       root  226r   DIR        8,1     4096     131926 /mnt/usbflash/others
famd       3861       root  227r   DIR        8,1     4096     131927 /mnt/usbflash/sounds
famd       3861       root  228r   DIR        8,1     4096     131928 /mnt/usbflash/videos
famd       3861       root  229r   DIR        8,1     8192     131929 /mnt/usbflash/Images
root@kinky:/home/hitu # pkill -9 famd
root@kinky:/home/hitu # umount /mnt/usbflash/
umount: /mnt/usbflash: device is busy
umount: /mnt/usbflash: device is busy
root@kinky:/home/hitu # lsof | grep usbflash
kdeinit   14459       hitu  129r   DIR        8,1    16384          1 /mnt/usbfl ash
root@kinky:/home/hitu # kill 14459
root@kinky:/home/hitu # umount /mnt/usbflash
root@kinky:/home/hitu #

Hope that helps :P