When Microsoft announced its Windows Virtual Desktop (WVD) spring 2020 refresh in April, one promised piece was missing from its checklist: MSIX App Attach. Officials at that time declined to say when and how this touted new feature would be available. It turns out it's here, in public preview now, for those with the Windows 10 May 2020 (2004) Enterprise feature update.
MSIX App Attach enables users to skip having to maintain multiple master images for different applications and/or the ability to package all their virtualized apps into a single image. App Attach enables packaged applications to be stored outside a virtual machine so that each application can attach itself when users need it. It's a step beyond traditional app layering and app streaming, according to Microsoft execs, and is a key piece of Microsoft's strategy to separate user data, apps and the underlying operating system
By adding App Attach, MSIX, the Windows packaging format Microsoft has been pushing for the past couple of years, gets more useful in virtualized environments like WVD. It's all about separating applications from the images, which means less re-imaging required; same package formats across an entire organization; and apps becoming indistinguishable from apps in the OS image, as described in this post by Christiaan Brinkhoff, a Global Black Belt for WVD at Microsoft (and former FSLogix employee).