UnoDOS pc64

Getting started

Download the ISO, write it to a spare USB stick with a tool you already know (Rufus, balenaEtcher) or boot it straight in a virtual machine — or use the one-click UnoDOS flasher. No building, no command line. (Just want a look first? Try it in your browser, nothing to install.)

What you need

  • A spare USB stick of any size (the image is tiny). Everything on it will be erased.
  • A 64-bit UEFI PC to boot it on, meaning essentially any x86-64 machine from about 2007 on.

Download the ISO and write it

Download unodos-pc64.iso

unodos-pc64.iso is a hybrid UEFI image: the same file boots as a virtual machine's CD-ROM and writes to a USB stick with any standard imaging tool.

With Rufus (Windows):

  1. Open Rufus and plug in the USB stick; pick it under Device.
  2. Click SELECT and choose unodos-pc64.iso. Leave the other options as they are.
  3. Click START. If Rufus asks how to write the image, choose Write in DD Image mode (an exact copy). Confirm the erase and wait a few seconds.

With balenaEtcher (Windows, macOS, Linux):

  1. Open balenaEtcher and click Flash from file; choose unodos-pc64.iso.
  2. Click Select target and pick the USB stick.
  3. Click Flash! and confirm.
This wipes the driveThe whole selected drive is erased. Double-check you picked the USB stick and not an internal disk before confirming.
Command line and raw imageOn Linux or macOS you can also write it with dd: dd if=unodos-pc64.iso of=/dev/<your-usb-disk> bs=4M. There is also unodos-pc64-uefi.img.gz, a raw disk image for the same tools. All downloads are on the releases page.

Or: the one-click flasher

The UnoDOS flasher does the download-and-write in one step - it carries the image inside it:

  1. Download it for your operating system:
    • Windows: UnoDosFlasher.exe. No install; it prompts for Administrator (raw disk writes need it).
    • macOS: UnoDosFlasher-macOS.zip. Unzip it and open UnoDosFlasher.app; it asks for your administrator password (raw disk writes need root). If macOS says it cannot verify the developer, allow it once under System Settings → Privacy & Security → Open Anyway.
  2. Run it and plug in your USB stick. The flasher picks the smallest removable disk automatically; check it is the right one.
  3. Click Install and confirm the erase. The flasher writes a bootable UnoDOS image to the drive.
The flasher on Windows: choose your USB drive and click Install.
The flasher on macOS: the same steps.
First launchThese builds are not signed with a paid developer certificate yet, so your OS may warn on first launch. On Windows, if SmartScreen appears, click More info → Run anyway. On macOS, right-click the app and choose Open the first time (Gatekeeper). The same applies to Rufus/Etcher warnings about an unrecognised image signature. Prefer to build it yourself? See the Developer guide.

Boot the target PC

  1. Plug the USB stick into the PC you want to run UnoDOS on.
  2. Turn off Secure Boot in firmware setup (steps below). The image is unsigned, so it will not boot with Secure Boot on.
  3. Restart, open the one-time boot menu (often F12, F9, F10 or Esc at power-on), and pick the USB stick.

Turning off Secure Boot

  1. Restart the PC and press the firmware-setup key at power-on. It is commonly Del on desktops and F2 on laptops (some use F1, F10 or Esc).
  2. Find Secure Boot, usually under a Security, Boot or Authentication menu, and set it to Disabled. Some firmwares first need you to set a supervisor/administrator password, or to switch the boot mode from "Windows UEFI" to "Other OS".
  3. Save and exit (usually F10).

When you are finished with UnoDOS, turn Secure Boot back on the same way to return the PC to normal.

BitLocker recovery promptIf the PC runs Windows with BitLocker: changing Secure Boot can make Windows ask for your BitLocker recovery key the next time it starts. This is reversible and does not erase anything. Enter the 48-digit recovery key (find it in your Microsoft account at aka.ms/myrecoverykey, or from your IT department), or simply turn Secure Boot back on to stop the prompt. To avoid it altogether, suspend BitLocker before changing Secure Boot (search Windows for Manage BitLocker, then Suspend protection) and resume it afterwards.

Try it in a virtual machine first

Prefer not to touch hardware yet? unodos-pc64.iso boots in any UEFI-capable hypervisor. In VirtualBox:

  1. New machine → Type Other, Version Other/Unknown (64-bit). A hard disk is optional - UnoDOS runs entirely from the ISO.
  2. Give it at least 256 MB of memory (the Other profile's default is too small).
  3. Settings → System → tick Enable EFI (special OSes only). UnoDOS is UEFI-native; without this the VM shows a black screen.
  4. Settings → Storage → put unodos-pc64.iso in the optical drive.
  5. Start. The splash, chime and desktop should appear in a few seconds. For sound, either audio controller works - UnoDOS has drivers for both Intel HD Audio and ICH AC97.
The ISO booted in a VirtualBox EFI virtual machine - the same desktop as real hardware, captured straight from the VM's screen.

Other hypervisors are the same idea: attach the ISO as a CD and boot with UEFI firmware - VMware (firmware type UEFI), Hyper-V (a Generation 2 VM with Secure Boot turned off), or QEMU + OVMF (see Build & run).

Install onto the PC (optional)

Running from the USB stick is fine forever - but the Install app (in the Start menu) can put UnoDOS on the computer itself, so it boots without the stick:

  • Onto an existing EFI partition (the rows marked keeps data): UnoDOS is copied into its own folder next to your other operating systems and added to the firmware boot menu. Nothing is deleted - Windows keeps booting as before, and you can undo it by deleting the \EFI\UNODOS folder.
  • Onto a whole disk (the Disk rows): the entire disk is erased and becomes a UnoDOS disk. This one cannot be done by accident - you have to type the word ERASE first (below).

Pick a target with ↑/↓ and press I to install (R rescans). The system files, fonts, documents and all the apps are copied along.

For a whole disk, one more step stands between you and an erased drive:

  1. Press C to put the caret in the confirm box (Esc leaves it again).
  2. Type ERASE.
  3. Press I to arm, then I again to commit.
A whole-disk install erases everything on that diskTyping ERASE is the only thing that unlocks a whole-disk install, and it applies to the selected row only - change the selection and you type it again. A row listed [too small], [read-only] or [not 512B/s] cannot be installed to at all. If you change your mind, press Esc and close the window; nothing is written until the second I.
The Install app. The key line across the top is the whole procedure, and the type ERASE box above the buttons is the gate on a whole-disk install - until that word is typed, I does nothing. This shot is from the emulator, which offers no disk UnoDOS can install to, so the list is empty; on a real PC each eligible disk and EFI partition appears as a row.

First boot

A splash screen with a loading bar appears while UnoDOS starts up, then a short start-up chime plays as the desktop appears - through the machine's sound hardware (HD Audio or AC'97) on a modern PC, or the PC speaker on machines that have one. On a laptop the TrackPoint, touchpad and keyboard all work.

The boot splash, with a loading bar and version.
First desktop paint: the Control Panel opens over the Aurora Light desktop.

From here, everything is a keystroke away. The Start button, a right-click on the desktop, or Ctrl+Esc all open the programs menu; arrow keys and Enter launch apps; Ctrl+W closes a window. The desktop tour covers the rest.

Want to build UnoDOS from source instead of flashing a prebuilt image? That's in the Developer guide.