Installation

Requirements

The app is free and doesn't require an account. Intel-based Macs are not supported. FFmpeg is needed only for video conversion — how to install it. Synchronization over the local network may need the system's permission or open ports in the firewall — local network.

macOS

Download and install

1. Download the FlyingFiles-1.7.4.dmg image with the button on the product page.

2. Open the downloaded file — a Finder window with the FlyingFiles app appears.

3. Launch FlyingFiles from that window. On first launch, macOS asks whether you're sure you want to open an app downloaded from the internet — click Open.

4. The app asks: “FlyingFiles is running from a disk image. Install it in your Applications folder?” Click Yes.

5. FlyingFiles copies itself to ~/Applications (the Applications folder in your user account) and restarts from the new location. You can now eject and delete the disk image.

Tip: The app is signed with a Developer ID certificate and notarized by Apple, which is why macOS doesn't warn you about it — it only asks once whether to open an app downloaded from the internet. If the system says the app is from an unidentified developer or is damaged, don't work around it — contact us, because it means something is wrong with the file.

Why ~/Applications and not /Applications

The /Applications folder is shared by the whole computer, and macOS lets only an administrator replace apps in it. An app installed there would ask for an administrator password on every update. In ~/Applications, updates go through without any prompts, and you can still find the app in Spotlight and in the list of apps.

If you previously dragged FlyingFiles to /Applications, the app works, but it won't move itself out of there. Quit it and, in Finder, drag it to the Applications folder in your home folder. If that folder doesn't exist, create it. The system may ask for your password.

Updating

Since version 1.5.0, the app checks nci.pl for a new version by itself every time you start it. It asks only when a new version is available. You can also check at any time:

1. Choose Help → Check for Updates….

2. The app checks nci.pl for a new version. If there is one, it asks: “Version X is available (you have Y). Download and install it now?”

3. After you click Yes, a window with a progress bar opens: first “Downloading update: X%”, then “Installing update…”. Cancel stops the download. Once the update is installed, the app restarts.

You turn off the check at startup with the Check for new versions when the application starts field in File → Settings… → Appearance and language (more); the command in the Help menu keeps working. The app doesn't download or install anything without your consent. Your settings, connections and passwords stay as they are.

Warning: Updates work in the copy installed from the disk image. A copy launched any other way responds with “Updates work only in a version installed from a package.”

Uninstalling

1. Quit FlyingFiles.

2. Move ~/Applications/FlyingFiles.app to the Trash.

3. If you also want to remove your data: delete the ~/Library/Application Support/FlyingFiles folder (settings, connections, log, pairings) and, in Keychain Access, the entries named FlyingFiles FTP (server passwords) and FlyingFiles Sync (the settings synchronization key).

Windows

Installing from the Microsoft Store

1. Open the FlyingFiles page in the Microsoft Store or search for “FlyingFiles” in the Microsoft Store app.

2. Click Get (or Install).

3. Launch FlyingFiles from the Start menu.

The Store package is signed by Microsoft, so Windows doesn't show SmartScreen warnings.

Updating

The Microsoft Store installs updates, usually automatically. Since version 1.5.0, the app also asks the Store by itself at startup and offers to install when the Store has a newer version (you turn this off in File → Settings… → Appearance and language). To check manually: Help → Check for Updates… in the app (it asks the Store, then downloads and installs a newer version) or Microsoft Store → Library → Get updates.

Since version 1.3.0, the download and installation progress shows in a separate window with a Cancel button, and after the update is installed, the app asks whether to restart it right away. Yes closes the app (saving the settings) and starts the new version; No — you keep working, and the new version starts the next time you launch the app.

Uninstalling

1. Settings → Apps → Installed apps (on Windows 10: Apps & features) → FlyingFiles → Uninstall.

2. Your data stays on disk. To remove it: delete the %APPDATA%\FlyingFiles folder (paste this path into the File Explorer address bar), the %LOCALAPPDATA%\FlyingFiles folder (local network pairings) and, in Credential Manager → Windows Credentials, the entries ending in @FlyingFiles FTP and @FlyingFiles Sync.

Linux: Ubuntu and Debian

The version for Ubuntu and Debian is a .deb package for these systems and their derivatives — one build for ordinary computers (amd64) and one for ARM machines (arm64). On Fedora, use the .rpm package — see the next chapter.

Downloading and installing

Not sure which package you need? Run uname -m: x86_64 means amd64, aarch64 means arm64.

Download the package with the button on the product page and install it with apt. Use apt rather than dpkg -i — only apt pulls in the missing libraries:

sudo apt install ./flyingfiles_1.7.4_amd64.deb

Start the app from your applications menu or with the flyingfiles command. You can also open the package in App Center (Ubuntu) or Discover (KDE) and click Install — for the first installation. For now, App Center will not install a newer version over an older one (why).

To check that the file arrived intact, checksums for all packages are at /flyingfiles/releases/linux/SHA256SUMS:

sha256sum -c SHA256SUMS 2>/dev/null | grep flyingfiles

Why “Unknown publisher” and the security warning

In Debian and Ubuntu, trust rests on the repository, not on the file. A package from the distribution archive or a PPA comes with a list signed with a GPG key, so the system knows who released it and that nothing changed on the way. A package downloaded from a website has no such context, so App Center says plainly: I don't know who built this. You will see exactly the same message for Chrome, Zoom or Visual Studio Code packages downloaded from their vendors' sites.

Signing the package itself would change nothing — neither apt nor App Center verify signatures of individual .deb files by default. The message will disappear once FlyingFiles has its own apt repository, which we plan (no date yet). Until then, the checksum above confirms the file's identity.

App Center's Install button is greyed out

When FlyingFiles is already installed, App Center shows a greyed-out Installed button for a package with a newer version, and you cannot install it. This is a bug in App Center, not in the package: it treats the file as installed whenever any version of a program with the same name is on the system, even an older one. On a first installation the button works.

The App Center developers fixed this bug in October 2026 (issue #2190); the fix will reach Ubuntu with one of the next App Center updates. Until then, install the new version with apt, as described under Updating:

sudo apt install ./flyingfiles_1.7.4_amd64.deb

The Unknown publisher label next to the app name is unrelated — it is the warning described above, and it does not block the installation.

The message “Download is performed unsandboxed as root”

The full text reads: “Download is performed unsandboxed as root as file … couldn't be accessed by user _apt”. This is a warning, not an error — the package installs correctly.

apt downloads files as the unprivileged _apt user to limit the damage if a server serves something malicious. When you point it at a file on your disk, it tries to read it the same way — and since Ubuntu 21.04 home folders are 750, so another user cannot enter ~/Downloads. apt therefore warns that this time it reads the file as root. For a file you placed on your own disk this makes no practical difference; it appears for every .deb installed from a home folder.

To avoid the message, install the package from a folder everyone can read:

sudo mv flyingfiles_1.7.4_amd64.deb /tmp/
sudo apt install /tmp/flyingfiles_1.7.4_amd64.deb

Updating

A new version will not arrive through apt upgrade — FlyingFiles has no apt repository yet. The app keeps an eye on releases itself: at startup (since version 1.5.0; you can turn this off in Settings) and after Help → Check for Updates… it asks the website for the latest version number. When there is a newer one, it gives you the install command with the file in your downloads folder and your computer's architecture, e.g.:

sudo apt install ~/Downloads/flyingfiles_1.7.4_amd64.deb

Yes copies this command to the clipboard and opens the download page: download the package and paste the command into a terminal. Versions before 1.7.0 only offer to open the page. You install the new package exactly like the first one, so in the folder where it is, all you need is:

sudo apt install ./flyingfiles_1.7.4_amd64.deb

Your settings, connection list and passwords stay in place. For now, do not update in App Center — with an older version installed, its Install button is greyed out (explanation).

Uninstalling

sudo apt remove flyingfiles

Your data stays on disk. To remove it, delete the ~/.config/FlyingFiles folder, and remove the passwords in Passwords and Keys (Seahorse) — the “FlyingFiles FTP” entries and the “FlyingFiles Sync” synchronization key — or with these commands:

secret-tool clear service "FlyingFiles FTP" account "connection name"
secret-tool clear service "FlyingFiles Sync" account "fingerprint-key"

Where the files are

What Linux does not have

• Automatic updates — the app tells you about a new version, but you install the package yourself (see above).

• Cloud folders on the drive bar. The bar shows (since version 1.5.0) the root folder / and the disks mounted in /media, /run/media and /mnt; you open disks mounted elsewhere by typing the path.

• Disc burning needs the xorriso program. The package recommends it, so apt usually installs it together with FlyingFiles; if it's missing: sudo apt install xorriso.

• Video conversion needs the ffmpeg program. The package recommends it too; if it's missing: sudo apt install ffmpeg.

• You unmount and format drives by right-clicking them on the drive bar or from the panel's context menu on the drive's folder in /media/your-name — more. Formatting uses the UDisks2 service, which the package installs together with the app.

• Synchronization over the local network and the files of paired computers need a Secret Service keyring (GNOME Keyring, KWallet) and — with the firewall on — open ports (local network).

• The trash and the “Open with” command go through gio from the libglib2.0-bin package; on desktops without gvfs, moving to the trash may fail and the app will say so.

Linux: Fedora

The Fedora version is an .rpm package — one build for ordinary computers (x86_64) and one for ARM machines (aarch64). During installation it adds the FlyingFiles repository on nci.pl to your system, so new versions arrive on their own, together with system updates.

Downloading and installing

Not sure which package you need? Run uname -m — it prints x86_64 or aarch64, just like in the file name.

Download the package with the button on the app page and open it — Fedora shows it in Software, where you just click Install. In a terminal:

sudo dnf install ./flyingfiles-1.7.4-1.x86_64.rpm

Start the app from the Activities overview or with the flyingfiles command.

Installing straight from the repository

Instead of downloading a file, you can add the repository and install the app like any other:

sudo dnf config-manager addrepo --from-repofile=https://nci.pl/flyingfiles/releases/rpm/flyingfiles.repo
sudo dnf install flyingfiles

On the first install dnf asks you to import the key “NCI FlyingFiles packages <kontakt@nci.pl>”. Check that the fingerprint matches and confirm:

57F1 A6CE 9CED B653 651B  7C94 C243 D155 0DC9 D00C

Updating

Nothing to do. A new version shows up in Software → Updates together with system updates, and in a terminal this brings it:

sudo dnf upgrade flyingfiles

Help → Check for Updates… in the app also tells you that a new version is out and gives you this command. Your settings, connection list and passwords stay in place.

Every package is signed with the key above, and dnf checks the signature before installing. The key comes with the first package, so updates don't ask for consent. Package checksums are at /flyingfiles/releases/rpm/SHA256SUMS.

Uninstalling

sudo dnf remove flyingfiles

The repository file /etc/yum.repos.d/flyingfiles.repo goes away with the app. The signing key stays in the package database — remove it with sudo rpmkeys --delete 57f1a6ce9cedb653651b7c94c243d1550dc9d00c (Fedora 41 and later) or sudo rpm -e gpg-pubkey-0dc9d00c (Fedora 40). You remove the app's data the same way as on Ubuntu: the settings folder and the passwords.

Where the files are

The application, the command, the menu entry and the settings — the same as on Ubuntu (table above). In addition:

The other differences of the Linux version (a drive bar without clouds, formatting through UDisks2, the local network) are described in the Ubuntu chapter — except for updates, which on Fedora arrive on their own from the repository. The trash and “Open with” go through gio and gvfs, which every Fedora Workstation has. Disc burning needs xorriso — dnf installs it together with the package, because the package recommends it; should it be missing: sudo dnf install xorriso. The same goes for video conversion: the package recommends ffmpeg-free, and should it be missing — sudo dnf install ffmpeg-free (more below).

FFmpeg for video conversion

The Convert Video… command uses FFmpeg, a free program. It isn't included with FlyingFiles, and the rest of the app doesn't need it. When it's missing, the FFmpeg Not Found window gives the same command as the table below, with a Copy Command button.

After installing, click Check Again in that window — there's no need to close the app. FlyingFiles looks for FFmpeg by itself in PATH, in the Homebrew, winget, Chocolatey and Scoop folders and in the system folders. If you keep FFmpeg somewhere else, point to it with the Locate Program… button or type its path in File → Settings…, on the Preview and video tab, in the FFmpeg program field. Other ways to install it are described on the FFmpeg website.

On Fedora, the ffmpeg-free package has no x264 and x265 encoders — the full set comes with the ffmpeg package from the RPM Fusion repository. FlyingFiles offers only the codecs the installed FFmpeg can encode. More in the manual: The FFmpeg program.

Local network: system permission and firewall

Pairing computers, synchronizing settings over the local network and the files of paired computers (since version 1.5.0) use port UDP 28217 (discovering computers) and ports TCP 28217–28220 (encrypted connections; the app takes the first free one). If you don't pair computers, there's nothing to set up — the app then opens no port at all.

On Linux you also need a Secret Service keyring (GNOME Keyring, KWallet) with an unlocked collection — it holds the key the app uses to encrypt saved pairings. Without it, the Synchronization tab turns off the network part; moving settings with a file keeps working.

After installation

• On first launch, the app starts in the language of your system — English, Polish, Spanish, German or French; with any other system language it starts in English. You can change it at any time in the Language menu.

• At first, both panels show your home folder. Next: Getting started.

• Settings are saved automatically. Before the first save, the app makes a one-time copy of the settings file, settings.toml.bak.0, and on later saves it keeps the five previous versions (settings.toml.bak.1–.bak.5).