While using the Windows 7 USB/DVD Download Tool to create a bootable USB drive to use for reinstalling/repairing Windows, I ran into the following error message:
Windows 7 USB/DVD Download Tool error: We were unable to copy your files. Please check your USB device and the selected ISO and try again.
I found the following link to a discussion about the issue:
Following the steps proposed by user @Siva2007 resolved the issue for me. Open a command prompt with administrator privileges and type:diskpart
Then enter the following commands to identify and format the USB drive in question:
Microsoft DiskPart version 6.2.9200
Copyright (C) 1999-2012 Microsoft Corporation.
On computer: KJONES-WIN8
DISKPART> list disk
Disk ### Status Size Free Dyn Gpt
-------- ------------- ------- ------- --- ---
Disk 0 Online 931 GB 0 B *
Disk 1 Online 29 GB 0 B
Disk 2 Online 980 MB 0 B
DISKPART> select disk 1
Disk 1 is now the selected disk.
DISKPART> clean
DiskPart succeeded in cleaning the disk.
DISKPART> create partition primary
DiskPart succeeded in creating the specified partition.
DISKPART> select partition 1
Partition 1 is now the selected partition.
DISKPART> active
DiskPart marked the current partition as active.
DISKPART> format quick fs=fat32
100 percent completed
DiskPart successfully formatted the volume.
DISKPART> assign
DiskPart successfully assigned the drive letter or mount point.
DISKPART>
After completing these steps to format the target USB drive, I was able to use the Windows 7 USB/DVD Download Tool to successfully create a bootable USB drive. Also note that despite the name, this tool also works to create bootable Windows 8 USB drives.
Further information about diskpart: