---
level: start
order: 30
---

# First install, step by step

From an empty BIOS folder to games that start.

**You need:** internet and some free space. The installer says how much.

## 1. Open a terminal and paste

A **terminal** is a window where you type commands. Paste the line for your
system, then press Enter.

<Tabs syncKey="os">
<TabItem label="Windows">

Open the Start menu. Type **PowerShell** and open it.

```powershell title="PowerShell"
irm https://raw.githubusercontent.com/Abdess/retrobios/main/install.ps1 | iex
```

</TabItem>
<TabItem label="macOS">

Open **Terminal**. It is in Applications, then Utilities.

```sh title="Terminal"
curl -fsSL https://raw.githubusercontent.com/Abdess/retrobios/main/install.sh | sh
```

</TabItem>
<TabItem label="Linux">

Open a terminal.

```sh title="Terminal"
curl -fsSL https://raw.githubusercontent.com/Abdess/retrobios/main/install.sh | sh
```

</TabItem>
<TabItem label="Steam Deck">

Switch to Desktop Mode and open **Konsole**.

```sh title="Terminal"
curl -fsSL https://raw.githubusercontent.com/Abdess/retrobios/main/install.sh | sh
```

</TabItem>
<TabItem label="Android (Termux)">

Install **Termux**, a terminal app. Run these three lines in it.

```sh title="Terminal"
pkg install python
termux-setup-storage
curl -fsSL https://raw.githubusercontent.com/Abdess/retrobios/main/install.sh | sh
```

</TabItem>
</Tabs>

On Batocera, Recalbox and similar setups, see
[Get your files](../which-pack.md).

## 2. Check the folder it found

It shows your setup and its BIOS folder:

```
  Found <your setup> at <its folder>
```

- **Right folder?** Go on.
- **Wrong folder?** Press Ctrl+C. Run the command again with your folder
  after `--dest`:

<!-- os-tabs windows: --dest D:\path\to\bios -->
```sh
curl -fsSL https://raw.githubusercontent.com/Abdess/retrobios/main/install.sh | sh -s -- --dest ~/path/to/bios
```

## 3. Choose what to install

```
  Enter) install everything
  i) only what the installed cores read
  c) choose systems, cores and regions
  q) quit
```

**Enter** installs everything. **c** lets you pick consoles.

## 4. Wait

You can stop with Ctrl+C at any time. Run the command again to carry on.

## 5. Read the last line

- **`Done.`** `N files installed, M already up to date.` All files are in place.
- **`Finished with errors.`** Some files failed. Run the same command again.
  It retries only those.
- **`Nothing was installed.`** The lines above it say why. See
  [If it stops](#if-it-stops).

## What the command does

<!-- image: install-flow -->

## Check it later

Add `--check` to the same command. It changes nothing.

<!-- os-tabs -->
```sh
curl -fsSL https://raw.githubusercontent.com/Abdess/retrobios/main/install.sh | sh -s -- --check
```

All good when every file is present and none is wrong:

```
  109/109 present (109 verified, 0 wrong hash)
```

An empty folder also shows `0 wrong hash`, with `0/109 present`.

## Copy the BIOS files from your old card

Before you wipe the card your device came with, or after you moved to a new
one, plug the old card in and add `--from` with its folder:

<!-- os-tabs windows: --from E:\ -->
```sh
curl -fsSL https://raw.githubusercontent.com/Abdess/retrobios/main/install.sh | sh -s -- --from /media/me/OLDCARD
```

It copies the BIOS files it finds there, in any folder and under any name,
and downloads only the rest. Your old card is only read. The last line says
how many came from it:

```
  38 files copied from E:\, 4 downloaded, 2 still missing.
```

Files already in your BIOS folder but in the wrong place (a `bios` folder
inside `bios`, a name in capitals, a ZIP you never extracted) are put where
your emulators look, without `--from`.

## Undo

It keeps every file it replaces in a `retrobios-backup` folder, next to your
BIOS folder. The end of the run prints the line that puts them back.

## If it stops

### No supported platform detected.

At a terminal, a menu follows. Pick your setup by its number, then type its
BIOS folder, or press Enter for the usual one. A folder pasted with quotes
around it is fine.

With `--no-input`, or without a terminal, it stops and prints the command to
use.

### Error: Python 3.8 or newer is required.

The message shows the command that installs Python. Run it, then run the
installer again.

A RetroPie 4.8 image has Python 3.7.3, and its update command finds nothing
newer. Use the [RetroPie ZIP](../platforms/retropie.md#download) there,
unzipped into `~/RetroPie/BIOS/`.

### Error: the downloaded installer does not match its expected fingerprint.

The download was cut short. Nothing was changed. Run the command again.

### Cannot create ...

You do not have the right to write there. Do what the message says. It names
what to run.

### Not enough space on the drive holding ...

It stopped before writing. Free some space, or use `--dest` to pick another
drive.

### The game still does not start

See [When a game does not start](troubleshooting.md).

## Next steps

- [Get your files](../which-pack.md)
- [When a game does not start](troubleshooting.md)
- Details: [Reading the installer's output, line by line](installer.md#reading-a-run)