winapp-signing

Name: winapp-signing
Availability: InStock
Author: Microsoft

Generate, trust, and sign Windows app and MSIX certificates with the winapp CLI.

1.2k|68|Updated Jul 30, 2025

Search Tags:#trust #windows #publisher #signing #certificate #msix #dev-cert

Ready to run

npx skills add https://github.com/microsoft/winappCli --skill winapp-signing

💬 Prompt for ChatGPT / Claude Chat▼

Please help me install this Agent Skill.
Skill: winapp-signing
Source: https://github.com/microsoft/winappCli/tree/main/.github/plugin/skills/winapp-cli/signing
Command: npx skills add https://github.com/microsoft/winappCli --skill winapp-signing

SYSTEM DOCUMENTATION & REQUIREMENTS

What problem does it solve?

Create and manage code signing certificates for Windows apps and MSIX packages. Use when generating a certificate, signing a Windows app or installer, or fixing certificate trust issues.

Core Features & Use Cases

Generate a development certificate for local testing to sign MSIX packages and apps.
Install (trust) a certificate on this machine to allow installation of MSIX packages and executables.
Sign a Windows app, MSIX package, or installer, with optional timestamping for production validation.
Publisher matching and manifest-based auto-inference to ensure signature alignment across deployments.

Quick Start

Generate a development certificate with winapp cert generate, install it to trust the machine, and then sign your MSIX package.

Frequently Asked Questions about winapp-signing

High-intent search queries and answers about installing and using this skill.

FAQPage Schema

How do I create a development certificate to sign MSIX packages for local testing?▼

To sign MSIX packages, generate a development certificate with winapp cert generate, install it to trust the machine, and then sign the package to ensure signature alignment across local testing deployments.

Why does my MSIX installation fail with a certificate trust error?▼

Certificate trust errors occur when the signing certificate is not installed on the target machine. Install the certificate to trust the machine, which allows proper installation of MSIX packages and executables.

Do I need administrator rights to install a code signing certificate for Windows apps?▼

Yes, administrator rights are required for installing a code signing certificate on a machine. The winapp CLI handles this process, which establishes trust for MSIX packages and executables across local deployment workflows.

Can I add a timestamp when signing a Windows app or installer for production?▼

Yes, optional timestamped signing is supported when signing Windows apps, MSIX packages, or installers. Timestamping ensures the digital signature remains valid for production validation even after the original certificate expires.

How does publisher matching work when signing an MSIX package?▼

Publisher matching uses manifest-based auto-inference to ensure the certificate signature aligns with the publisher declared in the package manifest, guaranteeing proper signature alignment across local testing and deployment workflows.