Sideloading Windows 8 Store Apps

This tip is an excerpt from an article entitled "Try It Out: Sideloading Windows Store Apps." To read the article in its entirety, visit the Windows Client TechCenter.

By now, you are familiar with Windows Store apps. There are some pretty cool ones available in the store, and publishers are adding more every week. A great thing about Windows Store apps is they are super simple to install (and uninstall). But what about line of business (LOB) apps? You probably do not want to publish them through the Windows Store since that would make them publically available.
Instead, you can sideload LOB apps. Sideloading simply means installing a Windows Store app without publishing it in and downloading it from the store. You install it directly.
There is some mythology around sideloading apps, possibly because many IT pros have yet to experience it firsthand. In reality, the process is super simple: it is nothing more difficult than running a few commands in Windows PowerShell. There are a few requirements that you have to set up in advance though, and those too are rather easy.
Here is the thing: The problem with seeing and doing this first hand is that you need to get your hands on an app that you can sideload. You cannot sideload an app you purchase from the Windows Store, and you might not be fortunate enough to have developers available who are working on them. So to get started, here is a checklist of the steps that can help you quickly and easily build your own app for testing purposes.

1. Set up the virtual machines – To experience sideloading for yourself, you will need two virtual machines (VMs): a domain controller and a client computer.
2. Create a Windows Store app – A Windows Store app is one that you can sideload so they are not just "floating around." As Microsoft does not recommend downloading apps from untrusted sources, the best alternative for trying out sideloading apps is to build an app. This is likely far easier to do than you would expect.
3. Install the root certificate – If you were deploying an actual LOB app, the developer would sign it with a certificate that is chained to a trusted root certificate. However, since you are just testing an app that is using a self-signed certificate, you need to install the root certificate on the client VM.
4. Verify the requirements – There are a small number of requirements computers must meet to sideload Windows Store apps on them. For a computer running Windows 8 Enterprise, the computer must be joined to the domain, you must enable the "Allow all trusted apps to install" Group Policy setting, and the app must be signed by a \ certificate that is chained to a trusted root certificate.
5. Sideload the app for a user – Sideloading the sample app for a single user is no more difficult than running a few commands in Windows PowerShell. However, if another user were to log onto the computer, the app would not be available to them.
   OR
   Sideload the app for all users – You can sideload an app for all users by using the Deployment Image Servicing and Management (DISM) tool. DISM is a command-line tool that you can use to service a Windows image–online or offline. If you are not familiar with DISM, see the Deployment Image Servicing and Management Technical Reference.

This is just a quick overview of the steps you would to take to experience sideloading Windows Store apps firsthand. For step-by-step guidance on how to complete step, please see Try It Out: Sideloading Windows Store Apps.