Frequently Asked Questions

It's not a virus — it's Windows SmartScreen being cautious. Because FretTool is a small, independently-built app without an expensive Extended Validation (EV) code-signing certificate, Microsoft flags it with a warning the first time you run it.

If you downloaded FretTool from the official GitHub releases page, it's safe. To get past SmartScreen:

1. When you see "Windows protected your PC", click More info.
2. Then click Run anyway.

Windows will remember your choice and won't bother you again.

That's Gatekeeper doing its job. Because FretTool isn't notarized by Apple (that costs $99/year), macOS blocks it on first launch. Here's how to open it:

1. Open the .dmg file and drag FretTool to your Applications folder.
2. Find FretTool in Finder (don't double-click it yet).
3. Right-click (or Control+Click) the app and choose Open.
4. A dialog will say it's from an unidentified developer — click Open anyway.

You only need to do this once. After that, it'll launch normally.

Tip: If dragging to Applications doesn't work, you can also run it from your Downloads folder — same right-click → Open trick applies.

The AppImage probably isn't marked as executable. Fix it in a terminal:

1. Navigate to where you downloaded the file.
2. Run chmod +x FretTool-*.AppImage
3. Double-click it again — or just run ./FretTool-*.AppImage from the terminal.

Some file managers also let you right-click → Properties → Permissions → "Allow executing file as program".

FretTool has a built-in updater. Go to Dashboard → Settings → About and click Check for Updates. If a new version is available, you'll be prompted to download it.

You can always grab the latest release directly from GitHub too.

Your projects live in FretTool's app data folder:

• Windows: %APPDATA%/FretTool/
• macOS: ~/Library/Application Support/FretTool/
• Linux: ~/.local/share/FretTool/

You can export individual projects as JSON from the dashboard if you want to back them up or move them to another machine.

PyInstaller (the tool that bundles Python apps into executables) has a bootloader that some antivirus programs heuristically flag as suspicious — even though it's harmless. It's a well-known issue affecting tons of open-source Python apps.

If your antivirus quarantines FretTool, you'll need to add an exception. The app is open source — you can inspect every line of code yourself.

The current builds are for x86_64 processors. Apple Silicon (M1/M2/M3) Macs can run them through Rosetta 2 — macOS will offer to install it automatically the first time you open the app.

Native ARM builds aren't available yet, but it's on the roadmap.

Yep — 100% free and open source (MIT licensed). No ads, no telemetry, no paywalls. If you'd like to support development, there's a Support Us page, but it's entirely optional.