How can we help?

Step by step

1. On the website, click “Download for Mac”: the file that suits your Mac is offered.
2. Open the .dmg file in your Downloads folder.
3. Drag KairOS into the Applications folder.
4. Open KairOS from Applications. If macOS shows a message on first launch, right-click KairOS, then “Open”.

Good to knowWhich version? Apple menu, then “About This Mac”. macOS 14 Sonoma or later: the standard file. Otherwise: the macOS 12 and 13 file.

Step by step

1. Click “Download for Windows”.
2. Open KairOS-Setup.exe from your Downloads folder.
3. If Windows shows “Windows protected your PC”, click “More info”, then “Run anyway”.
4. Click “Install”. KairOS opens by itself and starts with Windows.

Good to knowAfter that, KairOS updates itself, with no uninstalling or reinstalling.

Step by step

1. Open System Settings, then Privacy & Security.
2. Choose “Full Disk Access”.
3. Switch KairOS on in the list (add it with + if it is missing).
4. Relaunch KairOS, then run the analysis again.

Good to knowWithout this access, some folders (Desktop, Documents, Downloads) cannot be read.

Step by step

1. Open “Smart Scan”, the first entry of the menu.
2. Click the round “Scan” button.
3. Look at the result: trash bins, junk files, installers.
4. Click “Clean” to send everything to the Trash, or open a card to choose yourself.

Step by step

1. When a new version is available, the gorilla appears with an “Update” button.
2. Click it: KairOS downloads, installs and restarts by itself.
3. “Later” hides the reminder for 24 hours.

Good to knowYou can also download the latest version again from the Download page and install it over the old one.

Step by step

1. Open Cleanup › Duplicates.
2. Choose “Identical files” (same content, even under another name) or “Similar photos”.
3. Tick the folders to search, or “Whole Mac”. “Add a folder” adds more.
4. Set “Ignore below” to skip small files.
5. Click Start.

Good to knowAnalyses carry on if you change page: the percentage shows in the menu.

Step by step

1. Each line is a file with several copies: name, number of copies, recoverable space.
2. Click to open it: copies are grouped by folder, with a readable name (“Passports”, “Visits › May 2024”).
3. The “Recommended” badge marks the suggested copy: the oldest, often the original.
4. The ℹ︎ button gives the full path, the magnifier opens it in Finder, the thumbnail opens a preview.

Step by step

1. For each copy, choose Keep or Remove.
2. One copy always stays: KairOS refuses to remove every copy of a file.
3. Top menu: No selection, Smart selection, Keep the newest.
4. Click “Review before removing”: a summary appears.
5. Confirm: files go to the Trash and you can restore them.

Good to knowCopies in OneDrive, iCloud or Dropbox are never ticked automatically: removing them can also remove them from your other devices. Apps’ internal files are locked. Right before removing, KairOS checks every file again.

Step by step

1. Choose “Similar photos” before starting.
2. KairOS compares how photos look, not their names.
3. The largest, so best quality, is recommended.
4. Open the preview to compare before removing.

Step by step

1. Open Cleanup › Large Files and start the search.
2. Each line shows the file type, its origin (your files, app, temporary files, installer, backup, developer tool, system) and a sentence of explanation.
3. The risk badge: “Safe”, “Check first” or “Protected”.
4. The origin chips filter the list, for example to see only what is safe.

Good to knowA “Protected” file belongs to the system: it cannot be selected.

Step by step

1. Open Cleanup › Disk Space.
2. The colour bar shows what fills the disk: apps, documents, photos and media, developer, app data, trash, system.
3. Hover a segment to see its size.
4. Follow the three steps: Analyze, Free up space, Check the disk’s health.

Good to knowSizes are measured in the background, then remembered for the next launch. “System and other” is everything else.

Step by step

1. Empty the Trash: the space only comes back afterwards.
2. In Disk Space, look at the “Hidden macOS backups” line: temporary Time Machine copies can hold space.
3. Click “Delete them”: macOS asks for your password.
4. Wait a few minutes: macOS also frees “recoverable” space by itself.

Step by step

1. Open Cleanup › Downloads, then Analyse.
2. The chips filter by type, with their size.
3. Sort by size, age or name, or search a file by name.
4. Use quick select: installers, older than 30 days, older than 90 days.
5. Click “Move to Trash”.

Good to knowOnly installers are ticked at first.

Step by step

1. If at least 8 files lie loose, a message offers to tidy the folder.
2. Click “Yes, tidy up”: KairOS creates Images, Documents, Videos, Audio, Archives, Installers, Other, and puts each file in it.
3. An animation shows the files joining their folder. Wait a few seconds.
4. At the end, “Undo tidying” puts everything back.

Good to knowOnly loose files move: your folders and apps stay where they are, downloads in progress are not touched, and no file is overwritten.

Step by step

1. Start an analysis, then go wherever you like: it carries on.
2. The percentage shows in the left menu, next to the page concerned.
3. Come back to the page: the result is there.
4. One analysis at a time: if you start another, KairOS asks you to wait.

Good to knowThe percentage is an estimate, based on your last analysis.

Step by step

1. Click the thumbnail, or the eye.
2. The file shows large.
3. “Open” opens it in its own app.

Good to knowArchives, installers and programs have no preview.

Step by step

1. Open Protection, then “Run the analysis”.
2. KairOS checks startup items, downloaded files and your system’s signatures.
3. A threat that is found can be quarantined, then restored.
4. The scheduler runs the analysis on the days and time you choose.

Good to knowKairOS adds to your system’s protections, it does not replace them.

Step by step

1. Your files, photos and passwords stay on your computer.
2. The app only sends anonymous statistics: model, version, pages opened.
3. You can switch them off in the app.
4. All the details are on the Privacy page.

Step by step

1. Look at the badge: “Protected” or “App-managed” means KairOS does not offer it.
2. Allow Full Disk Access (the “Getting started” guide).
3. Close the app that uses the file, then try again.
4. If the problem continues, write to us with the file name.

Step by step

1. Pick a specific folder rather than “Whole Mac”.
2. Raise “Ignore below” to skip small files.
3. Leave the window open: the analysis carries on even if you change page.
4. Later analyses are faster.

Step by step

1. Check that both computers are on the same Wi-Fi.
2. Check that the 6-digit code is the same on both screens.
3. An interrupted transfer resumes where it stopped: start it again.
4. On Windows, allow KairOS through the firewall if Windows asks.

Step by step

1. Quit and reopen KairOS.
2. If nothing appears, download the latest version from the Download page.
3. Install it over the old one: your settings are kept.

Step by step

1. Mac: quit KairOS, then drag it from Applications to the Trash.
2. Windows: open “Installed apps” and uninstall KairOS.