Install app package manually

In this article, I will show you how to install a UWP app package along with its certificate and dependencies. A UWP package contains all the information required for a UWP, WinUI 3 or Win32 packaged app to install on your system.

UWP apps are packaged into bundles that contain all the required dependencies to be installed. When downloading such a bundle online, you might expect it to be easy to install, but it’s not always a straightforward task. This article will help you fix the most common problem: missing certificates. When opening a UWP app bundle, you may see this error appear:

Here’s how to properly install a UWP package:

Method 1 - Using the Certificate Installer For MSIX

Step 1 - Download the Certificate Installer for MSIX

Step 2 - Open the program and navigate to the certificate file

Step 3 - Press install

If the certificate has been succesfully installed, the window will close automatically. If the certificate needs a password to be installed, please contact the developer and ask them to give you the password.

Method 2 - Manual installation

Step 1 - Import app certificate

Before you begin the installation of an untrusted Universal Windows Platform (UWP) package, it’s crucial to ensure that the app’s certificate is properly imported into your system. If the app package comes with a certificate file, this step is necessary to validate the package and allow for a smooth installation. To import the certificate, simply double-click on it. After the window below opens, follow the next steps.

Now, click the “Install Certificate…” button. This action will open the Certificate Import Wizard, which will guide you through the process of adding the certificate to your system.

Make sure to select the “Local Machine” option and click “Next”. This ensures that the certificate is installed for all users on the system, granting the app the necessary permissions to run properly.

Select "Trusted Root Certification Authorities" to proceed. This step is crucial because it adds the app's certificate to the system's trusted root store, which means that Windows will recognize the certificate as valid and secure for UWP apps. Once you've made this selection, click "OK" to confirm and move forward with the installation process.

Click "Finish" to proceed.

Step 2 - Install dependencies

If the app comes with another package that contains dependencies, you might need to install that one as well. Since these dependencies are mostly Microsoft runtimes, they don’t require a certificate.

Step 3 - Install the app

Now that all the required dependencies have been installed, you can install the app package.