[[!meta title="Resetting a USB stick or SD card using Mac OSX"]]

[[!inline pages="doc/first_steps/reset.intro" raw="yes"]]

<div class="caution">

<strong>You might overwrite any hard disk on the computer.</strong> If at some
point you are not sure about which device to choose, stop proceeding.

</div>

1.  Make sure that the USB stick or SD card that you want to reset is unplugged.

2.  Start <span class="application">Disk Utility</span>.

    A list of all the storage devices on the computer appears in the left pane
    of the window.

3.  Plug the USB stick or SD card that you want to reset.

    A new device appears in the list of storage devices. This new device
    corresponds to the USB stick or SD card that you plugged in. Click on it.

4.  In the list of storage devices, verify that the device corresponds
    to the device that you want to reset, its brand, its size, etc.

5.  To reset the device:

    a. If there is an <span class="guilabel">Erase</span> tab
    in the right pane, click on it and then click on the <span class="button">
    Erase</span> button on the bottom right

    b. If there is an <span class="button">
    Erase</span> button on the top middle, click on it.

6.  In the confirmation dialog, click on the <span class="button">Erase</span>
    button to confirm.

<div class="note">

<p>If the erase process fails, try [[!toggle id="format"
text="formatting the USB stick using the command line"]] first.</p>

</div>

[[!toggleable id="format" text="""
<span class="hide">[[!toggle id="format" text=""]]</span>

Troubleshooting
---------------

Format using the command line
-----------------------------

<!-- Note for translators: This section is very similar to /install/mac/usb. -->

1. Unplug the USB stick from the computer.

1. Open <span class="application">Terminal</span> from
   <span class="menuchoice">
     <span class="guimenu">Applications</span>&nbsp;▸
     <span class="guisubmenu">Utilities</span>&nbsp;▸
     <span class="guimenuitem">Terminal.app</span></span>.

1. Execute the following command:

       diskutil list

   It returns a list of the storage devices on the system. For example:

       $ diskutil list
       /dev/disk0
         #:                     TYPE NAME         SIZE      IDENTIFIER
         0:    GUID_partition_scheme             *500.1 GB  disk0
         1:                      EFI              209.7 MB  disk0s1
         2:                Apple_HFS MacDrive     250.0 GB  disk0s2
         3:                      EFI              134.1 GB  disk0s3
         4:     Microsoft Basic Data BOOTCAMP     115.5 GB  disk0s4

1. Plug the USB stick in the computer.

1. Execute again the same command:

       diskutil list

   Your USB stick appears as a new device in the list. Check
   that its size corresponds to the size of your USB stick.

       $ diskutil list
       /dev/disk0
         #:                     TYPE NAME         SIZE      IDENTIFIER
         0:    GUID_partition_scheme             *500.1 GB  disk0
         1:                      EFI              209.7 MB  disk0s1
         2:                Apple_HFS MacDrive     250.0 GB  disk0s2
         3:                      EFI              134.1 GB  disk0s3
         4:     Microsoft Basic Data BOOTCAMP     115.5 GB  disk0s4
       /dev/disk1
         #:                     TYPE NAME         SIZE      IDENTIFIER
         0:   FDisk_partition_scheme             *4.0 GB    disk1
         1:                Apple_HFS Untitled 1   4.0 GB    disk1s1

1. Take note of the *device name* of your USB stick.
   In this example, the USB stick is 4.0 GB and its device name is <span class="code">/dev/disk1</span>.
   Yours might be different.

   <div class="caution">
   <p>If you are unsure about the device name, you should stop proceeding or
   <strong>you risk overwriting any hard disk on the system</strong>.</p>
   </div>

1. Execute the following command to safely remove the USB stick. Replace <span class="code">[device]</span>
   with the device name found in step 6.

       diskutil unmountDisk [device]

2. Execute the following command to format the USB stick. Replace <span class="code">[device]</span>
   with the device name found in step 6.

       sudo fdisk -iy [device]

1. You can try to reset the USB stick again using
   <span class="application">Disk Utility</span> from the beginning of this
   page.

"""]]
