optiSCAN

Free and open-source antivirus and PC optimizer for Windows, powered by ClamAV and YARA.
No account, no ads, no telemetry.

English · Français

Why optiSCAN?

Most "free" antivirus products push upgrades, collect data or show ads. optiSCAN is a Windows app that puts two well-known open-source detection engines, ClamAV and YARA, behind a clean interface, and adds the everyday cleanup tools people usually pay for. Everything runs locally, and the source code is here for anyone to read.

optiSCAN is designed to work alongside Windows Defender, not to replace it.

Features

Antivirus

• Quick, full, folder and file scans, with ClamAV and YARA running in parallel
• "Scan with optiSCAN" in the File Explorer right-click menu
• Risk score for every threat (critical, major, minor, informational)
• Encrypted quarantine (AES-256-GCM), with restore and delete
• Automatic signature and rule updates (ClamAV every 4 hours, YARA rules every 24 hours) after you download them once
• Optional real-time protection, automatic scan of USB drives and SD cards, scheduled daily scan
• Scan history with PDF and HTML reports
• Security score for your PC (firewall, UAC, Windows Update, shares) with one-click fixes

Optimizer

• Cleanup of temporary files, Windows logs, Recycle Bin and browser caches (Edge, Chrome, Firefox, Brave, Opera, Vivaldi, Arc)
• Application updates through winget, with older versions of the same program removed
• Performance, privacy and interface tweaks, with a button to restore the original settings

Interface

• English and French. The installer follows Windows: French or English with no prompt; it asks only if Windows is neither
• Light, dark and high-contrast themes, following the Windows theme by default

Screenshots

Antivirus	Signature updates
Cleanup	Tweaks
History and reports	Options
Light theme	French interface

Download and install

1. Download optiSCAN_Setup_v3.0.0.exe (about 66 MB) from SourceForge. The .NET 10 runtime is inside the installer; ClamAV and YARA signature databases are not — they download after install.
2. Run the installer. It uses French or English from Windows. If Windows is neither, pick one.
3. Open optiSCAN, go to Antivirus → Signatures and click Update to download the ClamAV signatures and YARA rules.

Requirements: Windows 10 version 1809 or later, or Windows 11, 64-bit.

Windows SmartScreen warning. This 3.0.0 installer is not code-signed, so Windows may show "Windows protected your PC". Click More info → Run anyway. Signed binaries are planned for 3.1 with SignPath Foundation; see the code signing policy.

How it works

optiSCAN.exe (WPF interface)
    ├── ClamAV  (clamd, or clamscan.exe as a fallback)  ─┐
    └── YARA    (rules compiled at first use)              ├── results merged, risk scored
                                                           ┘
optiSCAN.Service.exe (optional Windows service, SYSTEM)
    └── optiSCAN.Host.exe — real-time protection, USB scans

The engines run in a sandbox (AppContainer) without network access. AMSI script scanning is not in 3.0.0; it is planned for 3.1 with the signed service. The full technical guide, in French, covers the architecture, security model, build and release process: docs/GUIDE.md.

Build from source

git clone https://github.com/1donatien0/optiSCAN.git
cd optiSCAN
.\scripts\fetch-runtime-deps.ps1      # downloads ClamAV and YARA binaries
dotnet build optiSCAN.sln -c Release
dotnet test --project optiSCAN.Tests\optiSCAN.Tests.csproj -c Release

You need Windows 10 or 11 x64 and the .NET 10 SDK. Building the installer also needs Inno Setup 6; see section 8 of the guide.

Roadmap

Version 3.0.0 is the current public installer. Version 3.1 waits on code signing (SignPath): AMSI with the protection service, and signed binaries. See the release plan and the roadmap.

Contributing and support

• Questions and ideas: GitHub Discussions
• Bugs and false positives: open an issue
• Security vulnerabilities: please report them privately, as described in SECURITY.md
• Translations and code: pull requests are welcome. Interface strings live in optiSCAN.Engine/Resources/UiStrings.resx (French) and UiStrings.en.resx (English).

If optiSCAN is useful to you, a ⭐ on this repository helps other people find it.

License

optiSCAN is free software, released under the GNU General Public License v3 or later, without any warranty. Bundled components keep their own licenses (ClamAV: GPL-2.0, YARA: BSD-3-Clause); see the third-party notices.

Earlier versions. optiSCAN 1, 2 and 3 (tags v1, v2, v3) were first distributed under an end-user license agreement. Since October 16, 2026, their copyright holder has distributed them, source code and installers, under the GNU GPL v3 or later. This notice replaces the end-user license agreement found in LICENSE.txt in those commits.

Made by Donatien Byakombe (Dona By) in Vanier (Ottawa), Canada.