Subject: bug#41792: dd function – message: "No boot sector on USB device""

From: Ricky Tigg <[email-masked]>
Date: Wed, 10 Jun 2020 18:49:28 +0300

*Component*: coreutils.x86_64  8.32-4.fc32.; *OS*: Linux Fedora

Source of file:
https://www.microsoft.com/en-us/software-download/windows10ISO

Disc image file
- checked against its SHA-256 checksum was correct
- written successfully with that command:
# dd if=Win10_2004_Finnish_x64.iso of=/dev/sdc bs=4M oflag=direct
status=progress && sync

Once written, the partition is as follows:
$ mount | fgrep /run/media/$USER
/dev/sdb on /run/media/yk/CCCOMA_X64FRE_FI-FI_DV9 type udf
(ro,nosuid,nodev,relatime,uid=1000,gid=1000,iocharset=utf8,uhelper=udisks2)

While the USB device was booted in BIOS, the following message was
produced  "*No boot sector on USB device*"".

Using *Gparted*, while the device's partition was unmounted, the flags
could not be managed thus no boot flag was added. The following warning was
present:
*2.66 GiB of unallocated space within the partition.*