Unattended installation of Avast

This page presents a solution to deploying Avast Free unattended by repackaging it into Windows Installer (MSI) format without bundle products. The problem with Group Policy deployment is that the installation of Avast is not in MSI format, which is a requirement. This page will go through how to convert the installation to MSI format without using unreliable snapshots. Read on below for a step-by-step repackaging guide. You can also deploy without repackaging at all. Read on for details.

Repacking with FastTrack adds a new and exciting feature to Group Policy deployments. You can add launch conditions to prevent installation on some computers in the Group Policy OU or container.

Similar articles exist for TeamViewer, MalwareBytes, AVG and Microsoft Security Essentials.



Please note that if you deploy the free version of Avast, you are responsible for checking whether you fulfill the current conditions to use it for your purpose or not.


The first step is to start the EXE-to-MSI wizard (also known as Deployment Package Wizard). Simply start the "EXE to MSI" icon on the Home screen.

Home Screen EXE to MSI Generator

On the second page of the wizard, the type of output package must be selected. Here we must select Avast in the list. There are templates for TeamViewer, Avast, AVG, MalwareBytes and Microsoft Security Essentials, but you can repack any type of installation using the top two options; see instructions for this further down this page. The templates options are basically just extended versions of the generic EXE-to-MSI, which is the first option in the list.

The current setup file must be downloaded from www.avast.com. Click the free download link to get the current setup files. The downloaded file is named "avast_free_antivirus_setup.exe" or similar. Place this exe file in the directory that you specify as the setup file directory. The wizard will look for an exe file starting with "avast_" in this directory.

Avast MSI package

Convert to MSI or not?

At this point you need to decide, how to deploy Avast. You have two options. One is to continue the wizard and you end up with an MSI file. The other options is to use the checkmark at the bottom.

Saving script for unattended deployment

FastTrack Automation Studio can actually deploy software without a central management system. If you tick the checkmark, the wizard will save the generated script files instead in the folder, where you have the Avast setup file. Then you can click the "Software Deploy" icon in the Home Screen and simply point to the script file instead using the "Add FSH" button shown in the screenshot below. Refer to this page for more information on automated software deployments.

Software Deployment Install Page

MSI repackaging

Clicking next will show launch condition options. These options allows you to prevent installation of Avast on certain computers, such as servers. This means that you can deploy the package to an entire OU or container in your Active Directory with Group Policies and avoid having it install on for example servers and virtual machines.

Avast MSI package

The first page lets you block on hardware and operating system. The second launch condition page lets you block based on Active Directory information:

Active Directory launch conditions in an MSI file

To understand how launch conditions can actually work with Group Policies, we have to look at what the wizard does. There are generally four scenarios to create MSI files with FastTrack Automation Studio, as shown below. What we are doing here is using the option to the left. The MSI that wraps around the Avast setup file is always installed, but it does not do anything other than register as an program in the Windows programs list, if it hits a launch condition blocking. This means that from the point view of Group Policies or SCCM, the installation is always successful and will therefore not try to resend the MSI file. This is why there was also an option on the first page to use a setup MSI file inside the controller MSI, because then you can let the controller MSI always install, but only install the setup MSI on certain conditions, essentially allowing you to deploy all your software to all computers using Group Policies.

Avast MSI package

Clicking next in the wizard after launch conditions will ask you for name of the output MSI file. This is the controller MSI file that contains the Avast installer. When successful, the complete page is shown. Notice how it displays a script that you can open in the Script Editor and edit. Essentially the wizard does nothing more than compile this script and your Avast setup file as an MSI file. If you are not happy with the installation script or your need to expand it with, say licensing information, you can just open and edit the template script in the Script Editor and save it to the same folder as the Avast setup file. You are now using the third box in the drawing above, where you build your own custom MSI package. This is explained in a more detail at the bottom. Note that if you used launch conditions, you will see that conditions were inserted at the top of the script, which is why it is a good idea to let the wizard create a template script, in case you need to extend or modify the functionality.

TeamViewer MSI package

That's it! You now have an MSI file that will install Avast unattended, which you can now assign as a software installation to Group Policy (see screenshots below). As a general principle for Group Policy MSI deployment, you should check the uninstall option, to make sure that your MSI file will uninstall on all machines, if you remove the GPO MSI package.

Note that if you are using a trial version of FastTrack Automation Studio, the package will only deploy to 5 computers, as this is what the trial edition allows - the rest will behave similar to launch conditions, where the setup exe is not executed.

Similar articles exist for TeamViewer, MalwareBytes, AVG and Microsoft Security Essentials (click the links to see documentation).

Install software through GPO

Setting uninstall option for software through GPO

Expanding the script

If you need to modify or expand the script generated by the wizard, you must check the "Create a new script using the above template" on the last page of the wizard and save it to the same folder as your Avast setup exe file. Once you have modified the script to your needs, you must use the "Compile to MSI" option in the top menu.

Creating MSI file from project

The MSI generation wizard will open, as shown below. Make sure that you check "Include additional files from my project folder inside the MSI file". When you get to the page to select additional files inside the MSI file, make sure to check your Avast setup exe file. If you checked "Remove other Anvi-Virus products before install" in the wizard, you must also check the "Defer installation" setting, because MSI files may be executed on some machines during uninstall (see next section).

Avast MSI installation properties


If you checked the "Remove other Anvi-Virus products before install" checkmark in the wizard, the script will automatically uninstall AVG, MalwareBytes, Sophos and Security Essentials before running a new installation. The was this works is that a script snippet is included in the generated script. It uses the command "UninstallProgram" for these four products, which extracts the uninstall string for the product and then additional unattended switches are appended to it. If you need to uninstall more products, you can use the UninstallProgram command (in a custom compilation as explained in the previous section), but you will need to Google unattended uninstall switches, if the program stops and ask for information during uninstall. The example below is for MalwareBytes, where three additional switches ensures that there is no user interface and no questions. If the product is not installed, UninstallProgram does nothing. You can specify the whole name from the Windows programs list, or a left part such as using just "AVG" to ensure that it catches both AVG 2013 and AVG 2014.


If you need to uninstall Avast or Norton, you need to download uninstall utils from their web sites and include these in your custom compilation, as explained above. For most other Anti-Virus products, the method above using the UninstallProgram command is sufficient for a successful unattended uninstall.

Rating: 5 out of 5

"Use this as a replacement for VBScript and PowerShell"

"It's easy to include attractive GUI elements in FastTrack scripts, beyond the basic dialog boxes and text input that VBScript offers ... Another powerful feature is the ability to distribute scripts as Windows Installer (.msi) or standard .exe files. Although interesting in its own right, this ability results in a much more intriguing capability: to repackage -- or wrap -- software installers as .msi files without using snapshots. If you've ever created an .msi installer file from before-and-after system snapshots, for use with a software distribution system such as Group Policy or SCCM, then you know how hit-and-miss the results can be."

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Rating: 8 out of 10

"Faster than the rest"

"We found the FastTrack syntax to be more transparent and easier to learn than Microsoft's PowerShell – the editor in particular provided good support in this regard. the Script Editor offers a large number of options from the command set through to simple output of graphical elements, which cannot be achieved at all with PowerShell or other solutions or only with a significantly greater level of effort."

"Anyone wanting to tackle the many hurdles in everyday admin and especially anyone for whom logon scripts and client automation is a priority will benefit from the variety of functions offered by FastTrack."

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