Sideloading Modern Apps on Windows 8: A How-To Guide

Sideloading Unapproved Apps on Windows 8

Typically, Windows 8 users are limited to downloading applications exclusively from the Microsoft-approved Windows Store. However, Windows 8 provides two distinct methods for sideloading applications that haven't undergone official approval. These methods are primarily designed for developers and businesses utilizing internally developed apps.

It’s important to note that these techniques aren’t intended for general users seeking to install unapproved apps directly from the internet. Windows 8’s user interface mirrors Apple’s iOS in restricting unapproved software, contrasting with Android’s more permissive approach to sideloading.

This restriction applies solely to Modern apps within the new Windows 8 interface. Traditional desktop applications can still be installed through conventional means. However, desktop application installation is not possible on devices running Windows RT.

Acquiring a Developer License

Microsoft makes freely available developer licenses for Windows 8. These licenses empower developers to thoroughly test and evaluate their applications prior to submission to the Windows Store. While each license has an expiration date, renewal is possible to obtain a new license.

It’s crucial to understand that, as per Microsoft’s licensing terms, these licenses are exclusively for the development and testing of your own applications. Microsoft explicitly cautions against misuse:

“Microsoft can detect fraudulent use of a developer license on a registered machine. If Microsoft detects fraudulent use or another violation of the software license terms, we might revoke your developer license.”

To obtain a developer license, begin by opening Windows PowerShell with administrator privileges. This can be achieved by pressing Start, typing PowerShell, right-clicking the PowerShell shortcut, and selecting “Run as administrator.”

Enter the following command into the PowerShell window, press Enter, and accept the license agreement:

Show-WindowsDeveloperLicenseRegistration

You will then be prompted to provide your Microsoft account credentials, which will be linked to the developer license.

Once a developer license is secured, the following command can be executed in a PowerShell window to sideload a Modern application:

Add-AppxPackage C:\example.appx

Sideloading Within a Domain Environment

Windows 8 also provides a mechanism for sideloading “line-of-business” applications. This functionality enables organizations to deploy apps to their computers without making them publicly available through the Windows Store.

Four prerequisites must be met to successfully sideload a line-of-business app:

• Operating System Requirement: You must be running Windows 8 Enterprise, Windows Server 2012, Windows 8 Pro, or Windows RT. If using Windows 8 Pro or Windows RT, a “sideloading product activation key” must be purchased from Microsoft.
• Activation Key: Microsoft’s Volume Licensing page provides information on acquiring these keys.

If a sideloading product key has been obtained, open a Command Prompt window as an administrator and add the key using the following command, substituting ##### with the 25-digit key:

slmgr /ipk #####

Subsequently, execute the following command precisely to activate the sideloading key:

slmgr /ato ec67814b-30e6-4a50-bf7b-d55daf729d1e

Domain Membership: The computer must be joined to a domain to run the application. Even with Windows 8 Enterprise, a line-of-business app will not function unless the computer is connected to a domain.

Group Policy Configuration: Sideloading must be enabled through Group Policy. This setting can be configured either on the domain or the local computer.

To enable this setting on a local computer, press the Windows key, type gpedit.msc, and press Enter. Navigate to Computer Configuration\Administrative Templates\Windows Components\App Package Deployment within the Group Policy editor.

Double-click the “Allow all trusted apps to install” option and set it to Enabled.

Certificate Authority Trust: The app must be signed with a key from a certificate authority trusted by the local computer. Apps signed by established certificate authorities, such as Verisign, will install without additional configuration. Self-signed certificates require explicit trust on the local computer.

If all requirements are met, Modern apps can be sideloaded by executing the following cmdlet in a PowerShell window:

Add-AppxPackage C:\example.appx

Numerous misconceptions surround sideloading Modern apps on Windows 8. Simply enabling a Group Policy setting is insufficient. While developer licenses may appear to offer a workaround, Microsoft’s license agreement restricts their use to app development. Furthermore, these licenses are subject to monitoring, and access to apps could be revoked if used for unauthorized sideloading.