tauri-apps/tauri · error

Could not read binary file.

Error message

Could not read binary file.

What it means

In tauri-bundler's patch_binary, after bundling the app the bundler re-reads the compiled application binary to overwrite the __TAURI_BUNDLE_TYPE_VAR__ token with the package type (deb/rpm/appimage/msi/nsis). This expect fires when std::fs::read on the binary path returns an Err — the file is missing, moved, locked, or unreadable at patch time.

Source

Thrown at crates/tauri-bundler/src/bundle.rs:88

    crate::PackageType::MacOsBundle | crate::PackageType::Dmg => {
      // skip patching for macOS-native bundles
      return Ok(());
    }
    _ => {
      return Err(crate::Error::InvalidPackageType(
        package_type.short_name().to_owned(),
        "macOS".to_owned(),
      ))
    }
  };

  log::info!(
    "Patching {} with bundle type information: {}",
    display_path(binary),
    package_type.short_name()
  );

  let mut file_data = std::fs::read(binary).expect("Could not read binary file.");
  let bundle_var_index =
    kmp::index_of(BUNDLE_VAR_TOKEN, &file_data).ok_or(crate::Error::MissingBundleTypeVar)?;
  file_data[bundle_var_index..bundle_var_index + BUNDLE_VAR_TOKEN.len()]
    .copy_from_slice(bundle_type);

  std::fs::write(binary, &file_data).map_err(|e| crate::Error::BinaryWriteError(e.to_string()))?;

  Ok(())
}

/// Generated bundle metadata.
#[derive(Debug)]
pub struct Bundle {
  /// The package type.
  pub package_type: PackageType,
  /// All paths for this package.
  pub bundle_paths: Vec<PathBuf>,
}

View on GitHub (pinned to 52e4b6e71d)

Solutions

1. Rebuild from scratch with tauri build (or cargo tauri build) so the binary exists immediately before patching
2. Check the exact path in the preceding log line 'Patching <path> with bundle type information' and verify it exists and is readable
3. Confirm the binary name matches productName/binary in tauri.conf.json and the --target triple passed to the CLI
4. On Windows, exclude the target directory from antivirus/Defender real-time scanning

Example fix

# before — bundling against a target dir whose artifacts were removed
cargo clean && tauri bundle

# after — let tauri build produce the binary right before bundling
tauri build --bundles deb

// Rust — before invoking bundling programmatically
let binary = std::path::Path::new("target/release/my-app");
if !binary.is_file() {
  anyhow::bail!("app binary missing at {} — run cargo build first", binary.display());
}

When it happens

Trigger: Running tauri build/bundle when the app binary path recorded for patching no longer exists (target dir cleaned or artifacts moved mid-run), when another process (antivirus, indexer) holds an exclusive lock on Windows, or when permissions deny read access to target/<profile>/<app>.

Common situations: Build hooks (beforeBuildCommand/afterBuildCommand) or scripts that move/delete artifacts between the cargo build and bundling phases; antivirus quarantining unsigned exes on Windows; binary name mismatch between tauri.conf.json (productName/binary) and the --target/features actually built; permission-restricted CI runners.

Related errors

• failed to read binary path
• asset protocol path "{path}" is not valid: {e}
• File does not exist at path: {path}
• Missing OS permission to access path "{path}": {e}
• Unexpected target triple {}

AI-assisted analysis of tauri-apps/tauri@52e4b6e71d (2026-08-20). Data as JSON: /api/errors/5c90d9c1dac1077b. Report an issue: GitHub.