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Using App-V Package Accelerator to virtualize tricky apps

Here are some tips on using the Package Accelerator feature in Microsoft App-V 4.6 SP1 to virtualize tricky apps and pitfalls to avoid when sharing Package Accelerators you’ve built.

If you have ever used Microsoft’s App-V Sequencer tool to sequence an application for virtualization you know the sequencing process is normally pretty easy. However, not all applications work right when virtualized.

For example, App-V has trouble sequencing applications that do not support custom installation paths or that have complex or non standard installation processes.

To make sequencing tough apps faster and simpler, Microsoft introduced a new feature in App-V 4.6 SP1 called App-V Package Accelerators. The basic idea behind this tool is that once someone figures out how to sequence a particularly tricky application, they can create a Package Accelerator which automates the sequencing process for that application.

It is important to realize that a Package Accelerator is not a full blown installation package. It is essentially a set of instructions that tells App-V how to sequence an application. Package Accelerators can be shared with others in an effort to make it easier for them to package certain applications and there are already Package Accelerators available for products such as Microsoft Office 2010 and Adobe Reader that can be download from various websites, including TechNet.

Using App-V Package Accelerators
App-V Package Accelerators can be used in two different ways. First, you can use them to create an installation package. To do so, you would typically download the Package Accelerator you need from the Internet and then import the accelerator into the App-V sequencer where it is combined with your installation media for the application to create the installation package.

You can also create your own Package Accelerators for applications you need them for and share those accelerators with others.

Regardless of how you choose to use the App-V accelerator, testing is essential. Although the process for creating an accelerator is simple, there are a number of pitfalls that you have to watch out for.

If you are creating your own App-V Package Accelerator and you plan to share it with others, you will have to make sure you don’t accidentally include any sensitive information within your accelerator. Microsoft recommends that you attempt to create the accelerator directly from the application’s installation media. If that doesn’t work, you will have to install the application locally to create the accelerator. It is this installation process that opens the door for sensitive information to accidentally be included in the accelerator.

For example, if you choose to specify a product key while you are creating an accelerator, and then you share the accelerator with others, you have just given your product key to the world. Likewise, you should also be careful about including user account names or passwords within accelerator files. This can happen if you are forced to install an application locally in order to create an accelerator and the application makes use of service accounts.

In this type of situation, your best option is to tell the application to use the Local System account as the service account if possible. Keep in mind that Microsoft discourages using the Local System account as a service account for some applications (such as SharePoint 2010) because doing so could result in a service receiving excessive permissions. If you are forced to use a domain account as a service account within an application, you should avoid sharing the accelerator with others.

Regardless of whether an application uses service accounts or not, Microsoft recommends that you log in using the built-in administrator account when you create the accelerator for an application. The computer on which the application is being installed should also be assigned a generic name. These steps help to avoid exposing user names or computer names that are specific to your network.

When you create an accelerator, you are also required to include a guidance file; a TXT file or an RTF file that contains information about what the accelerator can be used for. You should type the guidance file before creating the accelerator, since you won’t be able to create the accelerator without a guidance file.

Although the bulk of this article has focused on things to watch out for when you create an accelerator, you also have to be careful about downloading accelerators that other people have created. It is entirely possible that an accelerator you download contains information that is specific to someone else’s network. It is also possible that the accelerator isn’t designed to package the full feature set that you intend to use. It might even be possible for an accelerator to contain malware infected files, so be careful.

Read more from Brien M. Posey

Brien M. Posey, MCSE, is a Microsoft Most Valuable Professional for his work with Windows 2000 Server and IIS. He has served as CIO for a nationwide chain of hospitals and was once in charge of IT security for Fort Knox. As a freelance technical writer, he has written for Microsoft, TechTarget, CNET, ZDNet, MSD2D, Relevant Technologies and other technology companies.

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