Q. Is there an easy way to make a USB device I can use to boot to DOS?

A. Even today, there are certain times I need to boot to DOS to perform a firmware or BIOS update. None of my servers has a floppy drive, however, so I want to boot from USB instead. I found a neat utility, BootDisk2BootStick, that takes an image of a bootable floppy and writes it to a USB drive. You can download it from Softpediathis page is apparently the utility's official site, but it's in German.

Pass the utility an image of a DOS bootable floppy and your USB device will be DOS bootable. You can then have various flash writing utilities and ROMs copied to it. Note that the utility formats the USB device at a size of around 1.44MB, no matter how large it really is. You need to make sure the USB device is empty, and I recommend doing a quick format just to make sure. The program doesn't work if data is found on the drive, though it doesn't give an error.

A search of the web for DOS boot images will find you lots of options that can be written to the USB device.

Click to expand.

Bootdisk.com has a nice image just for flashing a computer BIOS that leaves around 1.3MB of space for BIOS ROM flash files and the corresponding utilities.

Remember that if you're trying to flash your computer's BIOS, make sure it doesn't have a utility built into the BIOS to perform the flash without a special boot environment. Many motherboard makers now include easy BIOS update utilities, such as EZ Flash, that can be accessed by pressing ESC or another key, or through the BIOS Tools menu. In these cases, all you have to do is copy the BIOS image to a flash drive (FAT formatted, not NTFS), reboot the box, press the EZ Flash key, and your BIOS will be updated. Below is an example sequence for one of my computers.

Click to expand.

Related Reading:

Check out hundreds more useful Q&As like this in John Savill's FAQ for Windows. Also, watch instructional videos made by John at ITTV.net.
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