BigPizzaV3/CodexPlusPlus · error · anyhow::Error

GetPackagesByPackageFamily failed with {}

Error message

GetPackagesByPackageFamily failed with {}

What it means

Windows-only MSIX support in app_paths.rs enumerates packages for a package family via GetPackagesByPackageFamily using the two-call sizing pattern. The first call is made with a null buffer and must return ERROR_INSUFFICIENT_BUFFER (APPMODEL_ERROR_NO_PACKAGE or SUCCESS with count 0 are also accepted as 'no packages'). Any other Win32 status on this first call bails with the raw code number.

Source

Thrown at crates/codex-plus-core/src/app_paths.rs:160

        .encode_utf16()
        .chain(std::iter::once(0))
        .collect::<Vec<_>>();
    let mut count = 0u32;
    let mut buffer_length = 0u32;
    let first = unsafe {
        GetPackagesByPackageFamily(
            PCWSTR(family.as_ptr()),
            &mut count,
            None,
            &mut buffer_length,
            PWSTR(std::ptr::null_mut()),
        )
    };
    if first == APPMODEL_ERROR_NO_PACKAGE || (first == ERROR_SUCCESS && count == 0) {
        return Ok(Vec::new());
    }
    if first != ERROR_INSUFFICIENT_BUFFER {
        bail!("GetPackagesByPackageFamily failed with {}", first.0);
    }

    let mut pointers = vec![PWSTR(std::ptr::null_mut()); count as usize];
    let mut buffer = vec![0u16; buffer_length as usize];
    let status = unsafe {
        GetPackagesByPackageFamily(
            PCWSTR(family.as_ptr()),
            &mut count,
            Some(pointers.as_mut_ptr()),
            &mut buffer_length,
            PWSTR(buffer.as_mut_ptr()),
        )
    };
    if status != ERROR_SUCCESS {
        bail!("GetPackagesByPackageFamily failed with {}", status.0);
    }
    buffer.truncate(buffer_length as usize);
    buffer

View on GitHub (pinned to fb3ebd9a82)

Solutions

1. Look up the numeric code from the message (map it with std::io::Error::from_raw_os_error) and check the family name being passed
2. Verify the family name shape Name_PublisherHash via PowerShell: Get-AppxPackage | Select PackageFamilyName
3. Confirm the package is registered for the current user with Get-AppxPackage <name>
4. If the status looks transient (resources/service), retry the enumeration once after a short delay

Example fix

// before
if first != ERROR_INSUFFICIENT_BUFFER {
    bail!("GetPackagesByPackageFamily failed with {}", first.0);
}

// after - include the readable Win32 message for diagnosis
if first != ERROR_INSUFFICIENT_BUFFER {
    bail!(
        "GetPackagesByPackageFamily failed with {} ({})",
        first.0,
        std::io::Error::from_raw_os_error(first.0 as i32)
    );
}

// Validate family-name shape before calling the AppModel API
fn valid_family_name(family: &str) -> bool {
    let mut parts = family.splitn(2, '_');
    matches!((parts.next(), parts.next()), (Some(n), Some(p)) if !n.is_empty() && !p.is_empty()
        && family.chars().all(|c| c.is_ascii_alphanumeric() || c == '.' || c == '_' || c == '-'))
}

let packages = match package_full_names_by_family(&family) {
    Ok(names) => names,
    Err(error) => {
        tracing::warn!("package enumeration failed ({error:#}); falling back to Program Files roots");
        windows_app_package_roots().into_iter().map(|root| root.join(app_folder)).collect()
    }
};

When it happens

Trigger: The sizing call returns something other than ERROR_INSUFFICIENT_BUFFER: ERROR_INVALID_PARAMETER for a malformed family name (missing or wrong publisher-hash segment), ERROR_INSUFFICIENT_RESOURCES, or ERROR_SUCCESS with count > 0 (only count == 0 success is accepted).

Common situations: A hardcoded or derived package family name with a typo; running on Windows Server or a stripped image without full AppModel support; corrupted package registration where Get-AppxPackage still lists the app.

Related errors

• GetPackagePathByFullName failed with {}

AI-assisted analysis of BigPizzaV3/CodexPlusPlus@fb3ebd9a82 (2026-08-17). Data as JSON: /api/errors/ebddf399d632e111. Report an issue: GitHub.