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I have created a liveUSB-stick with Xubuntu 12.04 on it. I installed Xubuntu from it on a MacBook Air. If I now plug in the usb stick, it is not recognized anymore. How can I make it recognized and format it in order to use it again as a normal storage USB stick?

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Plug it in and format it. – harisibrahimkv May 20 '12 at 12:44
Well, that was my idea. But I don't see the USB stick anywhere in the file system, it is not mounted in /media. And: How can I format it? – Marius Hofert May 20 '12 at 12:46
If you are using Linux, try the command "dmesg". It will show you whether the device has been detected or not. – harisibrahimkv May 20 '12 at 12:48
For how to format using the command line, check this:… – harisibrahimkv May 20 '12 at 12:50
okay, I saw with dmesg that /dev/sdc has 2 GB, so I guess that's my USB stick. I then tried sudo mkfs -t vfat /dev/sdc and obtained: "Device partition expected, not making filesystem on entire device '/dev/sdc' (use -I to override)". What am I doing wrong? – Marius Hofert May 20 '12 at 12:57
up vote 3 down vote accepted

here's some simple instructions just for your reference.

A. First we need to delete the old partitions that remain on the USB key.

Open a terminal and type sudo su
Type fdisk -l and note your USB drive letter.
Type fdisk /dev/sdx (replacing x with your drive letter)
Type d to proceed to delete a partition
Type 1 to select the 1st partition and press enter
Type d to proceed to delete another partition (fdisk should automatically select the second partition)

B. Next we need to create the new partition.

Type n to make a new partition
Type p to make this partition primary and press enter
Type 1 to make this the first partition and then press enter
Press enter to accept the default first cylinder
Press enter again to accept the default last cylinder
Type w to write the new partition information to the USB key
Type umount /dev/sdx1 (replacing x with your drive letter)

C. The last step is to create the fat filesystem.

Type mkfs.vfat -F 32 /dev/sdx1 (replacing x with your USB key drive letter)

That's it, you should now have a restored USB key with a single fat 32 partition that can be read from any computer.

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Thanks vicd for the details, exactly what I was looking for. I indeed now see the USB stick again :-) It has the strange name D4C4-DD6D. How (or where) could I have specified a normal name like "USB"? – Marius Hofert May 20 '12 at 13:13
Glad to hear you've solved this issue. To label your usb stick, feel free to use -n option, if you want to specify a name like "USB", try this command mkfs.vfat -F 32 -n USB /dev/sdx1 – vicd May 20 '12 at 13:47
In addtion, you can get this done easily by using "Gparted Partion Editor"(default installed in ubuntu), that's a GUI way without re-formating it :-) The ONLY thing you need to pay attention is to unmount your usb stick before renaming it. – vicd May 20 '12 at 13:52

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