Kairo.Your old PC. Fast again.

Since 14 October 2025, Windows 10 no longer gets regular security updates, and Windows 11 doesn’t run on many older PCs. Instead of buying a new PC, you can install Kairo: it keeps getting security updates, is built for older PCs and comes with a browser, office and email. Try it for free from a USB stick first – nothing changes on your PC.

Yes, under the hood: Kairo is built on Debian 13, one of the most proven Linux systems, and gets its security updates from there. You won’t notice that in everyday use – Kairo has its own simple interface that works like a modern PC. You never need a command line.

Every program opens as a window, just like you know it from Windows: you can minimise, maximise and close it, and the desktop stays visible. Running programs appear as icons right next to the Kairo button – one click brings the program to the front. In addition, a slim bar at the top shows all open and minimised windows. Two windows side by side: right-click the icon and choose “Links anordnen” or “Rechts anordnen” (arrange left or right), press the Windows key with the left or right arrow, or simply drag the window to the edge. The Windows key with the up arrow gives a window the whole space.

New in 0.9.1:

• Files in Kairo style: folders, USB sticks and the bin in one window, with tabs – bring back deleted files with one click, flip through photos with the arrow keys.
• Light or dark: every tier comes in both – switch in the control centre or under Einstellungen › Aussehen (appearance).
• 100 games by Kairo: cards, puzzles, board games against the computer, platformers and brawlers – no ads, no internet, several at once in tabs.
• Window bar at the top: bring open and minimised programs to the front with one click.

Since 0.9: every program is a real window, plus:

• Printing: set up a printer with one click under Einstellungen › Drucker (Settings › Printers).
• Second monitor, TV or projector: under Einstellungen › Bildschirme (Settings › Displays), mirror, extend or use just one. Kairo remembers this for each monitor.
• Screenshot with the Print key – it goes to Bilder › Bildschirmfotos (Pictures › Screenshots).
• Notifications from programs appear above the windows. With “Nicht stören” (do not disturb), it stays quiet.
• Default programs: you choose what opens websites, PDFs, pictures and more.
• Backup to a USB stick: you choose the folders, and Kairo puts them in the folder “Kairo-Sicherung” on the stick.
• Programs from the app shop update themselves in the background.
• Find files: the Kairo search also finds files by their name.
• Accessibility: strong contrast and a screen magnifier (Ctrl + Alt + Plus or Minus).

None of this slows Kairo down: the print service only runs while you need it, and no search service runs in the background for finding files. You don’t need a licence for these new features.

If it has a 64-bit processor and at least 2 GB of memory, there’s a good chance. With 1 GB, Kairo starts in the Feder tier – so far we have only tested that in an emulator. We are only just starting to test Kairo on real older PCs. You’ll know for sure after testing from the USB stick – it costs nothing and changes nothing. How to check this in Windows is under requirements.

Many older ones do: with “Windows-Programme” you install old Windows games and programs, also from CD images (.iso, .cue/.bin). Before installing, Kairo shows a traffic light: runs, PC too weak, or doesn’t run. Newer games with copy protection or anti-cheat don’t run. For a lot of things you don’t even need them: well-known programs are already built in – a browser for browsing, LibreOffice for texts, tables and presentations, and Outlook for email and appointments. Services like Microsoft 365, WhatsApp, YouTube or your online banking work in the browser. More programs like VLC or Zoom are free in the app shop.

Yes. Kairo has LibreOffice built in: “Schreiben” (writing) opens and saves Word files, “Tabellen” (tables) Excel files and “Präsentation” PowerPoint files. Very elaborately designed files may look a little different than in Microsoft Office.

Not for trying and installing. For browsing, the app shop, updates and activating the licence, yes – via Wi-Fi or cable.

Not yet. Kairo’s screens are in German for now, and the built-in programs such as the browser and LibreOffice are set up in German. Websites and web apps appear in the language you choose on them. The installer lets you choose your keyboard layout.

When you try Kairo from the USB stick, your hard drive stays unchanged – after restarting, everything is as before. Kairo doesn’t show your Windows files; bring important files along on a USB stick. When installing, “Erase disk” (“Festplatte löschen”) is preselected: then all data on it is gone. With “Install alongside” (“Daneben installieren”), Windows stays, if there is enough free space. Back up your photos and documents first in any case.

No. Built in are drivers for graphics from AMD, Intel and NVIDIA, sound for many laptops and Wi-Fi chips from Intel, Realtek, Atheros, MediaTek and many from Broadcom and Marvell. Under Einstellungen › Geräte und Treiber (Settings › Devices and drivers) you can see what was detected. The self-test there checks sound (with a test tone), brightness, graphics, touchpad and Wi-Fi. You set up mouse and touchpad under Einstellungen › Maus und Touchpad: speed, tap to click and natural scrolling. Try from the USB stick whether everything works on your PC. You set up printers under Einstellungen › Drucker (Settings › Printers) and a second monitor under Einstellungen › Bildschirme (Settings › Displays). You pair Bluetooth devices under Einstellungen › Bluetooth (Settings › Bluetooth).

Yes. From the USB stick: pull out the stick, restart, done. If you chose “Install alongside” (“Daneben installieren”), you can choose between Kairo and Windows when starting. If you erased the disk, you need a Windows installation medium from Microsoft and a valid licence to switch back.

We do. Write to office@automata.at and briefly describe which PC you have and what happens. We reply as quickly as we can. Many answers about starting from the stick are also in the guide.

On installed PCs, Kairo fetches the security updates from Debian 13, which it is built on, by itself in the background – even without a licence. Debian plans them until 2028, limited until 2030. Your programs from the app shop also update themselves in the background. New Kairo versions only arrive checked and signed: for 30 days after installing so you can test them, after that with a licence at no extra cost. There are no updates when running from the USB stick.

For the first 30 days after installing, everything is unlocked. After that, Kairo keeps running: all built-in programs, your data, your installed programs and web apps (including their updates) and the security updates from Debian. Without a licence, though, there are then no new Kairo versions, no new programs or web apps from the app shop, and only the Feder and Essenz tiers – Kairo shows this in the top bar as “Ohne Lizenz” (without licence). With a licence key (Einstellungen › Updates und Lizenz, i.e. Settings › Updates and licence), everything is unlocked again. The same applies if a licence was refunded or blocked. Nothing is restricted when running from the USB stick.

One PC. When you activate it, the licence is linked to that PC. New PC or reinstalled Kairo? Write to us and we’ll release the licence for the new installation.

Not for Kairo – but you still need to be careful. Windows viruses don’t run on Kairo: almost all malware is made for Windows, and Kairo is Linux (Debian). Programs only come from Kairo, from Debian and from Flathub, and programs from the app shop run sandboxed. Without your password, no program can change the system files, and on installed PCs security updates arrive by themselves. A classic virus scanner would be a burden on old PCs: ClamAV, for example, needs more than 1 GB of memory just for its virus list, according to its own documentation.

Most damage today comes from fraud, not viruses: fake emails (“your parcel is waiting”), fake shops, calls from supposed technicians. No protection catches everything. Don’t open links in unexpected emails, and only enter passwords and bank details on sites you opened yourself.

When you open a website, Kairo asks the non-profit service Quad9 (Switzerland) for its address – in all programs, including E-Mail and programs from the app shop. Known malware and scam sites then don’t open at all. The requests are encrypted when the network allows it; in a hotel or on a train with a sign-in page they continue unencrypted so that signing in works. You can switch the protection off under Einstellungen › Sicherheit (Settings › Security). The Wächter (Guard) shows whether it is running.

E-Mail is Outlook on the web from Microsoft. The spam filter and warnings about scam emails come from Microsoft; Kairo’s website protection works on top and keeps known scam sites away, even when you click a link in an email. Here too: no filter catches every scam email.

The browser is Chromium from Debian – the basis of Google Chrome – and, on installed PCs, gets fixes by itself with the security updates. Kairo sets it up like this: no usage statistics, no Google sign-in, no outside extensions, and search via DuckDuckGo.

On installed PCs, your folders Documents, Pictures, Desktop, Music and Videos – every 15 minutes when something has changed and there is enough free space. With Time Travel you open an earlier version in Files and bring it back with “Zurückholen” – the current file goes to the bin. The backups are stored on the same PC: they help if you deleted or overwrote something, but not if the hard drive breaks. So also back up important files to a USB stick – under Einstellungen › Sicherung auf USB-Stick (Settings › Backup to USB stick), into the folder “Kairo-Sicherung”. When running from the USB stick, the Guard backs up nothing.