App-V is Microsoft's application virtualization solution. App-V allows administrators to install applications within virtual machines on servers, and then stream the applications to multiple clients across the organization. The difference between an App-V application solution and a standard dumb terminal implementation is that applications served through App-V can be cached locally so that clients can continue using them if the connection to the virtual machine is lost. App-V applications run in "sandboxes," protecting the rest of the computer against local changes to the file system or registry. Also, since the applications run in a virtual sandbox on the client, end-users can run multiple versions of the same application, or run legacy applications that might not work correctly on a more current operating system running on the local PC.

To help troubleshoot local App-V client problems, there are two main areas available: Content Storage and Windows Events.

App-V Content Storage

The App-V client utilizes local computer directories and the registry for important data storage. The content contained in the directories, files, and registry provides necessary information to enable virtual applications to run properly and to run as assigned by the administrator. Understanding where the data exists can help the administrator troubleshoot when there are problems.

The information that is stored on the local client, of course, takes up much less space than if the actual package were fully installed.

Here's where the App-V client stores its information:

App-V Windows Events

In addition to using the data storage locations for troubleshooting, the App-V client also logs information in the local Windows Event log. To locate App-V specific events, open the Even Viewer and looking under Applications and Services Logs\Microsoft\AppV\Client.

The App-V client will record three types of events: Admin, Operational, and Virtual Application.

The Admin event type records any general warnings and errors. The Operational event type chronicles the execution and usage of the individual App-V workings. The Virtual Application even type records the actual application launches.