Installing YouniqMail

Last updated October 2026

YouniqMail is available for macOS, Windows and Linux. The download lives at youniqmail.com.

Operating system:macOSWindowsLinux

Installing on macOS

1. Download the file ending in .dmg.
2. Open it with a double-click.
3. Drag YouniqMail into the Applications folder.
4. Launch the app from the Applications folder.

The app is notarized and signed by Apple, so the first launch should show no warning. If one appears anyway, you probably downloaded the file from a different source.

Apple Silicon only. There is no build for Macs with an Intel processor. Which processor you have is shown under Apple menu → About This Mac.

Installing on Windows

1. Download the file ending in .exe.
2. Start it with a double-click.

The installation runs through without further questions and sets up YouniqMail for your user account; you do not need administrator rights for it.

The app is signed, issued to Sven Hörig. If Windows shows a warning anyway, check under More info whether that name is listed as the publisher.

64-bit systems only. There is no build for 32-bit Windows.

Installing on Linux

There are three formats. The DEB and RPM packages are recommended, because they set YouniqMail up fully in the system. The AppImage is meant for systems that neither of them fits.

DEB package: for Debian, Ubuntu and related systems.

sudo apt install ./YouniqMail-*.deb

RPM package: for Fedora, RHEL, openSUSE and related systems.

sudo dnf install ./YouniqMail-*.rpm

On openSUSE:

sudo zypper install --allow-unsigned-rpm ./YouniqMail-*.rpm

AppImage: runs without installation.

1. Download the file ending in .AppImage.
2. Make it executable:

   chmod +x YouniqMail-*.AppImage

3. Start it with a double-click or from the terminal.

Notes on the AppImage

The AppImage needs FUSE, which most desktop systems ship. If it reports Cannot mount AppImage, the fuse3 package is missing:

• Debian and Ubuntu: sudo apt install fuse3
• Fedora: sudo dnf install fuse3
• openSUSE: sudo zypper install fuse3

On Ubuntu 24.04 or later the AppImage also runs without the sandbox that shields displayed emails from the rest of the system. Use the DEB package there instead.

Architectures: All three formats exist for x64 and ARM64. There is no build for ARMv7.

Links from other apps with the AppImage

For mailto: links and activation links to open YouniqMail, the app has to be registered with the system. The DEB and RPM packages do this automatically. With the AppImage you need a helper such as AppImageLauncher.

The Linux packages are not signed, so your system may show an unknown-source notice.

The first launch

On first launch, a wizard walks you through the setup:

1. Welcome
2. Appearance, Email List and Sound
3. Mail (when mails count as read) and Compose (undo send)
4. Default Mail App (optional)
5. Security: encryption of the local database, on by default, and you should leave it that way. It cannot be switched later.
6. Recovery Key: save it, see below
7. Complete

More on this under The setup wizard.

After that you set up your first account. See Adding an account.

This is what YouniqMail looks like once set up, with sidebar, message list and dashboard:

Really save the recovery key

It is shown exactly once during setup. Without it, your local database cannot be recovered if your system’s keychain is ever lost. You can display it again later under Settings → Security → Encrypt Storage and save it as a PDF.

Updates

YouniqMail checks for a new version at launch and regularly afterwards. Updates are not downloaded automatically: a window shows what is new, and you decide with Download now or Not now. Once the new version has been downloaded, Restart & install installs it right away; otherwise this happens the next time you quit YouniqMail.

System requirements

macOS from version 12 (Monterey) onwards, for Apple Silicon only. Windows 10 or 11 in the 64-bit edition. Linux in the common distributions from Ubuntu 22.04, Debian 12, Fedora 35, RHEL 9 or openSUSE Leap 15.6 and comparable onwards, as a package for x64 and ARM64.

Storage needs depend on the size of your mailboxes. The app itself is content with a few hundred megabytes; mail with attachments can add up to considerably more.