Application in use & Unpublish - App-V 5.1

Question : What happens when we unpublish an application that is in use in App-V 5.1? We see that the unpublish is getting failed, but when we launch the shortcut, it doesn't work.What is the issue?

Answer : Lets take an example by publishing the Mozilla Firefox App-V 5.0 package in a standalone machine using Powershell. Launched the shortcut and everything works fine. Now tried to unpublish by keeping mozilla firefox open(in-use).We are seeing the below "Currently in use" error.

We can see that the unpublishing has failed. Nothing has changed to the mozilla application. Shortcuts are seen in the Start menu etc. But when we try to launch the shortcut, we see this error.

When analyzed more by checking in event viewer, we see the below entry.

The package has been scheduled to be unpublished during restart/reboot. How this works?

The App-V client creates an entry in pendingtasks registry for the particular application with its ProductGUID_VersionGUID.

REASON: 

With App-V 5.0 SP2 or higher, App-V packages that are being used cannot be unpublished. It will be made to unpublish automatically during restart/reboot if globally published and unpublish during logoff/login if published to the user. This is handled by making a PendingTasks entry to the following registries.

Global Publish - HKEY_LOCAL_MACHINE\Software\Microsoft\AppV\Client\PendingTasks 

User Publish - HKCU\Software\Microsoft\AppV\Client\PendingTasks

Prior to App-V 5.0 SP2, Application in use cannot be unpublished. It can be done only by closing the application and then unpublishing it again.