--- title: About the connection group virtual environment (Windows 10) description: Overview of how the connection group virtual environment works. author: lomayor ms.pagetype: mdop, appcompat, virtualization ms.mktglfcycl: deploy ms.sitesec: library ms.prod: w10 ms.date: 06/25/2018 ms.reviewer: manager: dansimp ms.author: dansimp ms.topic: article --- # About the connection group virtual environment >Applies to: Windows 10, version 1607 ## How package priority is determined The virtual environment and its current state are associated with the connection group, not with the individual packages. If you remove an App-V package from the connection group, the state that existed as part of the connection group will not migrate with the package. If the same package is a part of two different connection groups, you have to indicate which connection group App-V should use. For example, you might have two packages in a connection group that each define the same registry DWORD value. The connection group that is used is based on the order in which a package appears inside the **AppConnectionGroup** XML document: - The first package has the highest precedence. - The second package has the second highest precedence. Consider the following example section: ```XML ``` Assume that same DWORD value ABC (HKEY\_LOCAL\_MACHINE\\software\\contoso\\finapp\\region) is defined in the first and third package. For this example, the DWORD value definition would be the following: - Package 1 (A8731008-4523-4713-83A4-CD1363907160): HKEY\_LOCAL\_MACHINE\\software\\contoso\\finapp\\region=5 - Package 3 (04220DCA-EE77-42BE-A9F5-96FD8E8593F2): HKEY\_LOCAL\_MACHINE\\software\\contoso\\finapp\\region=10 Since Package 1 appears first, the AppConnectionGroup's virtual environment will have the single DWORD value of 5 (HKEY\_LOCAL\_MACHINE\\software\\contoso\\finapp\\region=5). This means that the virtual applications in Package 1, Package 2, and Package 3 will all see the value 5 when they query for HKEY\_LOCAL\_MACHINE\\software\\contoso\\finapp\\region. Other virtual environment resources are resolved in a similar way, but usually collisions occur in the registry. ## Merging identical package paths into one virtual directory in connection groups If two or more packages in a connection group contain identical directory paths, the paths are merged into a single virtual directory inside the connection group's virtual environment. Merging these paths allows an application in one package to access files that are in a different package. When you remove a package from a connection group, the removed package's applications can no longer access files from packages in the connection group it was removed from. App-V looks up a file’s name in the connection group in the order App-V packages are listed in the connection group manifest file. The following example shows the order and relationship of a file name lookup in a connection group for **Package A** and **Package B**. |Package A|Package B| |---|---| |C:\Windows\System32|C:\Windows\System32| |C:\AppTest|C:\AppTest| When a virtualized application tries to find a specific file, App-V will first for a matching file path in Package A. If it doesn't find a matching path in Package A, it will then search Package B using the following mapping rules: - If a file named **test.txt** exists in the same virtual folder hierarchy in both application packages, App-V will use the first matching file. - If a file named **bar.txt** exists in the virtual folder hierarchy of one application package, but not in the other, App-V will use the first matching file. ## Related topics - [Managing Connection Groups](appv-managing-connection-groups.md)