Why is my USB stick not detected?

THE400 Mini requires a USB stick to be formatted with the FAT32 file system along with a Master Boot Record (MBR) or at least one partition. We recommend using a USB stick that is less than 32GB in size (see Using a USB stick that is larger than 32GB below for more information on creating a partition manually).

Note: You may also require a good branded power supply capable of supplying more than 1A to provide the USB stick with enough power. See Why does THE400 Mini reset… for further infomation.

You can either format the USB stick yourself as described below, or flash your stick with one of the pre-prepared USB stick images, see Using a pre-prepared USB stick image.

Formatting a USB stick to FAT32

Microsoft Windows

Recent versions of Windows will attempt to use exFAT or NTFS instead of FAT32, especially if the USB stick of a high capacity.

  1. Ensure your USB stick is no more than 32GB in size. Larger sticks cannot be formatted to FAT32 (see below).
  2. Use the Windows format utility, and select FAT32 from the File system menu.

MacOS

  1. Ensure your USB stick is no more than 32GB in size. Larger sticks cannot be formatted to FAT32 (see below).
  2. Use the Disk Utility application to erase and reformat your USB stick. Select a format of MS-DOS (the name MacOS uses for FAT32) and a Scheme of Master Boot Record (MBR).

Using a USB stick that is larger than 32GB

To use a USB stick larger than 32GB it must be split up in to multiple partitions of no more than 32GB each (partitioned).

THE400 Mini requires at least one partition present on the USB stick. This happens by default when you format the stick with an MBR. If you are unable to format the USB stick with an MBR with your operating system, or have a USB stick greater than 32GB, you will have to partition the stick manually.

Given the subtle differences in the partitioning and formatting tools provided by different operating systems and version, we refer you to the many detailed tutorials available online which explain how to partition and format a USB stick with the operating system you are using.

Note that THE400 Mini will only use the first partition of a USB stick, which must be no larger than 32GB and formatted as FAT32.