Install and upgrade

SpaceKnife is published on the Releases page. Each release has installers and portable archives for Windows, Linux and macOS, and SHA-256 checksum files for all of them. The interface follows the system language (English or Simplified Chinese); change it any time in Settings › General › Interface language.

Which file to download

System	File	What it is
Windows 10 or later, x64	SpaceKnife-<version>-Setup-x64.exe	Installer, for the current user or all users
Windows 10 or later, x64	SpaceKnife-<version>-win-x64-portable.zip	Portable: unzip and run, no installation
macOS 14 or later, Apple Silicon	SpaceKnife-<version>-mac-arm64.dmg	Disk image
macOS 14 or later, Intel	SpaceKnife-<version>-mac-x64.dmg	Disk image
Ubuntu 22.04 or later, Debian family	spaceknife_<version>_amd64.deb	Package
RHEL 9 or later, Fedora family	spaceknife-<version>.x86_64.rpm	Package
Other Linux, x64	SpaceKnife-<version>-x86_64.AppImage	Single file, needs FUSE 2
Linux, x64	SpaceKnife-<version>-linux-x64-portable.tar.gz	Portable: extract and run, no FUSE

Windows and Linux builds are x64 only; there is no 32-bit Windows build. The Linux builds need glibc 2.34 or later (the level of RHEL 9; Ubuntu 22.04 has 2.35).

Check the download

The in-app update checks the checksum for you (see Updates and privacy). To check a file you downloaded yourself, compare its SHA-256 with the line for that file in the release’s checksum files (SHA256SUMS.txt and the SHA256SUMS-portable-… / SHA256SUMS-mac-… files next to it):

Get-FileHash .\SpaceKnife-<version>-Setup-x64.exe -Algorithm SHA256

sha256sum -c --ignore-missing SHA256SUMS.txt

shasum -a 256 SpaceKnife-<version>-mac-arm64.dmg

Windows

Installer

1. Run SpaceKnife-<version>-Setup-x64.exe.
2. The installer isn’t code-signed yet, so on the first run SmartScreen warns about an unknown publisher. Click More info, then Run anyway.
3. Choose who it is for: only you (the default, no administrator rights needed) or all users (asks for administrator rights). You can change the install folder.

The installer speaks English or Chinese, following the system language. It creates Start menu and desktop shortcuts and can start SpaceKnife when it is done.

Current user or all users

A current-user install lives in a folder your own account can write to. The MFT quick scan starts its elevated, read-only scan helper from the install folder. If you want that program to sit where only administrators can change it, choose the all-users install (Program Files).

Silent install

For scripted deployment, the installer takes the usual switches:

.\SpaceKnife-<version>-Setup-x64.exe /S /currentuser

Use /allusers instead of /currentuser for a machine-wide install (run it as administrator). To uninstall silently, run the QuietUninstallString from SpaceKnife’s uninstall entry in the registry, which is "Uninstall SpaceKnife.exe" /currentuser /S in the install folder. The uninstaller copies itself to a temporary folder and runs from there, so the command returns at once. A silent uninstall keeps the snapshots, settings and logs; add --delete-app-data to remove them too.

Portable zip

Unzip SpaceKnife-<version>-win-x64-portable.zip somewhere you can write (your user folder, a USB drive; not Program Files) and run SpaceKnife.exe. The first launch takes a few seconds longer while Windows checks the new files.

Next to SpaceKnife.exe there is a data folder. While it is there, SpaceKnife keeps everything in it (snapshots, settings, logs, cache) and writes nothing to your user profile. See Portable mode.

macOS

Install

Open the dmg and drag SpaceKnife into Applications. You need macOS 14 or later; take the arm64 dmg for Apple Silicon and the x64 dmg for Intel Macs.

First launch: allow it once

The macOS build is not notarized by Apple yet, so macOS blocks it the first time:

1. Open SpaceKnife. macOS says it could not verify that SpaceKnife is free of malware. Click Done.
2. Open System Settings › Privacy & Security, scroll down to the message that SpaceKnife was blocked, and click Open Anyway. Click Open Anyway again and enter your password.

From then on SpaceKnife opens normally. After you install a new version, allow it once more.

Other ways to do the same:

• On macOS 14, right-click SpaceKnife in Applications and choose Open.
• In Terminal: xattr -dr com.apple.quarantine /Applications/SpaceKnife.app

Full Disk Access

Without Full Disk Access, macOS asks separately before SpaceKnife may read the Desktop, Documents, Downloads, iCloud Drive and other cloud drives, the Photos library, other apps’ data, and removable and network drives. A scan then brings up one prompt after another, and some places (Mail, Messages) can’t be read at all: they count as unknown space.

Before each scan (while Protected places is set to Ask before scanning, the default), SpaceKnife checks whether it has Full Disk Access; the check itself never brings up a prompt. If it hasn’t, the dialog Let SpaceKnife read every file at once offers three ways on:

Button	What happens
Open System Settings	Opens the Full Disk Access list. Switch SpaceKnife on (if it is not there, add it with +), then reopen SpaceKnife when asked. The scan doesn’t start.
Skip the protected places	Scans without any prompt; those places show as not accessible.
Scan and ask one by one	Scans, and macOS asks for each place.

Tick Remember “skip” or “ask one by one” before you click one of the last two buttons, and the dialog won’t come back. The choice is the setting Settings › Scan & performance › Protected places (Ask before scanning, Skip them, no prompts, Access them).

After each update

The build is ad-hoc signed, and macOS ties the permission to that exact build. After installing a new version, open the Full Disk Access list and switch SpaceKnife off and on again.

Scanning runs in a background process of SpaceKnife; macOS still shows its prompts and permissions under the name SpaceKnife.

Linux

deb and rpm

sudo apt install ./spaceknife_<version>_amd64.deb

sudo dnf install ./spaceknife-<version>.x86_64.rpm

Both put the program in /opt/SpaceKnife/, the spaceknife command in /usr/bin, and add SpaceKnife to the app menu with its icon. The package manager installs the dependencies (the usual ones of a desktop app: GTK 3, NSS and so on).

AppImage

chmod +x SpaceKnife-<version>-x86_64.AppImage
./SpaceKnife-<version>-x86_64.AppImage

The AppImage needs FUSE 2 (on Ubuntu 22.04, the package libfuse2). Without it, start it with --appimage-extract-and-run.

From 0.3.2 on, the AppImage carries update information: ./SpaceKnife-<version>-x86_64.AppImage --appimage-updateinformation prints it. AppImage update tools use it, and the .zsync file published next to the AppImage, to download only what changed.

Portable tar.gz

tar xzf SpaceKnife-<version>-linux-x64-portable.tar.gz
cd SpaceKnife-<version>-linux-x64-portable
./spaceknife

No FUSE needed. Like the Windows zip, it keeps all its data in the data folder next to the program (portable mode).

Newer Ubuntu releases

In the AppImage and the tar.gz, Chromium’s chrome-sandbox is not setuid. On distributions that restrict unprivileged user namespaces (the AppArmor rule Ubuntu has from 23.10 on), they may not start; run them with --no-sandbox. Ubuntu 22.04 and RHEL 9 are not affected.

Upgrading

SpaceKnife checks for new releases at most once a day and shows them in the title bar. It downloads and verifies the new version in the background; then the update card has two buttons. Seamless update (Windows installer, portable copy, AppImage) has SpaceKnife put the new version in place itself and open again; the classic way hands over to the installer, the disk image or the package, or lets you replace the file yourself. Nothing is installed until you click. How that works, how to skip a series and how to turn the check off: Updates and privacy.

Whichever way you upgrade, your scans, snapshots and settings stay: they live outside the program folder, or in the data folder of a portable copy.

Install	How the new version replaces the old one
Windows installer	Click Seamless update in the update card: SpaceKnife closes, the installer replaces the old version in the background without showing its pages, and SpaceKnife opens again. Run the installer instead quits SpaceKnife and opens the installer’s wizard, the same as running a newer installer by hand.
Windows or Linux portable	Click Seamless update: SpaceKnife puts the new program files in place itself and keeps the data folder. With Replace it yourself, or by hand: quit SpaceKnife, unpack the new archive and replace the contents of the old folder, but keep its data folder.
macOS dmg	Click Open the disk image: SpaceKnife quits and opens the disk image. Drag SpaceKnife into Applications to replace the old one. Then allow it once more and switch Full Disk Access off and on (see above).
deb or rpm	Click Open the package: SpaceKnife quits and opens the package in the system’s software installer. Or install the new package with apt or dnf as above.
AppImage	Click Seamless update: the new AppImage takes the place of the old file. With Replace it yourself, or by hand: quit SpaceKnife and replace the old file with the new one.

Uninstalling

Install	How to remove it
Windows installer	Uninstall SpaceKnife from the app list in Windows Settings. It removes the program, the window’s caches, the cache and the downloaded updates. Its second page, Your data, asks about the rest: tick Also delete the snapshots, settings and logs (unticked by default) to remove %LOCALAPPDATA%\SpaceKnife too.
Portable	Delete the folder. Its data folder goes with it.
macOS	Quit SpaceKnife and move it from Applications to the Trash.
deb	sudo apt remove spaceknife
rpm	sudo dnf remove spaceknife
AppImage	Delete the file.

Unless you tick that box, or remove a portable copy, your scans, snapshots and settings stay, so a later install picks them up again. To remove them by hand, delete the folders listed in Data locations. A folder set with SPACEKNIFE_HOME is never touched by the uninstaller.

The command line

Every installed copy also has the backend’s command line, for scans and snapshots in a terminal:

Install	Path
Windows	<install folder>\resources\backend\spaceknife-backend.exe
Linux deb or rpm	/opt/SpaceKnife/resources/backend/spaceknife-backend
macOS	/Applications/SpaceKnife.app/Contents/Resources/backend/spaceknife-backend

What it can do: Command line.