I've been asked to built a Windows computer recently that would have no DVD drive so I had to use the Windows 7 USB/DVD Download Tool to create a bootable USB stick with the Windows installer. Since I only have Macs at home I had to use my Windows XP virtual machine to create this and quickly ran into problems with the tool reporting 'unable to run bootsect to make the USB device bootable'. This is how I solved it.

This is the final screen that shows the error. The USB stick was created properly, the only issue is it is not bootable now.


To fix this, the bootsec.exe needs to be obtained and there are a few places to get it from, which I will not link here.

I think the Win7 DVD comes with the bootsect.exe, but since the Win7 DVD was 64 bit and I was using a 32 bit WinXP VM, it would not run.


My USB stick had the drive letter D assigned to it. So I used the following on the command prompt:


Note: the back slashes are not showing up so I've changed them to forward slashes for display purposes.

This updated the boot sector for the USB stick and I was able to boot from it and successfully install Windows.

-i