# Flashing BIOS with FreeDOS

## grant123

I know in the past I've been able to install FreeDOS to a USB stick with unetbootin, copy a BIOS .exe file to the stick, boot it, and run the executable to update my BIOS, but now I'm not seeing the .exe file with dir once the stick is booted.  I think I used to use "c:" or "cd c:" before running the .exe before but that tells me C isn't a valid drive.  Does anyone remember how to do this?

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## grant123

Any ideas with this one?  I researched but couldn't come up with anything.

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## Ant P.

It depends what the BIOS (and FreeDOS) thinks your USB drive is, and might be affected by hard disk partitions too. The letter it booted up showing should've been the correct one, though.

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## grant123

I think the way FreeDOS works is it boots to some kind of a floppy image and then you have to change virtual drives in order to access any files you've added to the USB stick.

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## khayyam

grant123 ...

I just did a bios update on a Dell D820 about a week ago. I first tried making my own freedos image (following the guide on the wiki) but this failed to boot to a prompt ... I tried both the grub2 method, and the sysresccd method, and built the .img two or three times, but no go. I then used Christian Taube's FreeDOS bootable USB, dd'ed it to a usb stick, copied the (unziped) bios update exe to the disk, booted and selected 'Load FreeDOS without drivers" and at the prompt run '\D820A10.exe'. The exe run and the bios was updated.

HTH & best ... khay

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## grant123

It was the partition type and filesystem.  I changed the partition type from linux to FAT32 and I was able to cd to C: but I still couldn't see the executable file.  So I reformatted the partition with mkfs.vfat and re-ran the FreeDOS installation from unetbootin and it worked perfectly.

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