As we discover more and more of Windows 8.1, it becomes clear this Windows Operating System has some tweaks to facilitate the adoption of it by end-users of Windows Operating Systems prior to Windows 8.
In this series, I’ve already shown you how to force a specific Start Screen Layout. I’ve also shown you how to theme the Windows 8.1 Start Screen and The New Interface altogether. Today I’ll show you how to control Start Screen App Pinning.
What’s New
In Windows 8, when you install an app or application, it shows up on the far right side of the Start Screen automatically. This process is called ‘pinning’ to the Start Screen. After you’ve installed a bunch of apps or applications, you would, typically, unclutter the Start Screen from apps and applications you don’t use regularly.
In Windows 8.1, this behavior is turned off, by default. When you install an app or application, it does not automatically get pinned to the Start Screen.
Managing Start Screen Pinning
Now, for colleagues running Windows 8, this behavior is counter-intuitive. They are already accustomed to the Start Screen getting filled with their apps. When your organization is still running Windows 7 and earlier, the non-automatically pinning behavior might be a good thing: Their Start Screen doesn’t get cluttered.
Tip!
You can also combat cluttering by using the Start Screen Layout policies, described here, although this will make colleagues unable to add or remove any items on their Start Screen and will override any changes made to the Start Screen before you applied the Group Policy setting.
To change the default behavior, we’ll create a Group Policy Object (GPO).
Open the Group Policy editor on a Domain Controller running Windows Server 2012 R2, or on a domain-joined Windows 8.1 installation equipped with the Remote Server Administration Tools (RSAT) to create the new Group Policy object (GPO).
Use Group Policy Management to create a new Group Policy Object (GPO). It is part of the Administrative Tools folder. In Group Policy Management (gpmc.msc), in the left pane, expand the Active Directory forest, then domains, and then your domain name.
Right-click Group Policy Objects and select New from the context menu. Give your new Group Policy Object a meaningful name and click OK when done.
Now, expand the Group Policy Objects node and select your newly created Group Policy Object. Right-click it and select Edit… from the context menu. In the left pane of the Group Policy Management Editor window, either navigate to User Configuration \ Policies \ Administrative Templates \ Start Menu and Taskbar or follow the same path under Computer Configuration. Here double-click the Pin Apps to Start when installed group policy setting:
When you enable this group policy setting, the Apps, whose App IDs are in the list of this group policy setting, will be pinned to the Start Screen automatically at installation time.
So now, all we need to put this policy to use, after we enabled it, is to add AppIDs.
An easy way to find out AppIDs for apps and applications would be to install the app or application for which you want to find out the AppID to a reference Windows 8.1 installation. Pin the app or application to the Start Screen manually. Then, use the Export-StartLayout PowerShell command to export the pinned applications. AppIDs for pinned apps are part of the output of this Cmdlet. (BIN or XML)
Note:
I haven’t found a way to make all apps and applications automatically pinable to return to the automatic pinning behavior as found in Windows 8.
Tip!
When you’ve implemented the Start Screen Layout, apps and applications in the list will not be pinned, when they’re not a part of the exported Start Screen Layout.
Click OK when done.
Concluding
This is the third part in this series, covering the Start Screen. It’s the last one, I promise. 
Further reading
All the new Windows 8.1 Group Policy Administrative Settings
Windows 8.1 Preview: new features, Group Policy, & thoughts
What’s New for the Enterprise in Windows 8.1
MSDN Library – AppID Key
What is AppID??
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