Skip MSI if already installed

Question

I have a WIX installer in which I install my program and .NET Core 1.0.5. The .NET Core is installed in silent mode:

<ExePackage InstallCommand="/q" Id = "DotNetCore.Setup" SourceFile="..\DotNetCore\DotNetCore.exe" />

On a clean system, the installer just goes fine. If I try to reinstall it, I get a reboot. Probably the .NET installer detected to be already installed and triggered the repair feature on its own. Is there any way to skip the .NET Core installation if it's already installed?

I tried looking for command line parameters but nothing seems useful

Answer 1

The ExePackage element has the DetectCondition property. This means that you can specify a condition such that, if the condition evaluates to false, the package will be installed. You can combine this with an util:RegistrySearch element which can be used to search through the registry to detect if the .NET Core has already been installed.

In order to perform the registry search, you will first need to find a registry key which is present whenever .NET is installed.

Find the "HKLM\\SOFTWARE\\Microsoft\\Windows\\CurrentVersion\\Uninstall\\", (or "HKLM\\SOFTWARE\\WOW6432Node\\Microsoft\\Windows\\CurrentVersion\\Uninstall\\" on 64-bit machines) key in your registry, then locate the subkey which corresponds to the .NET Core - this key should have a value for "DisplayName" which should be ".NET Core" or something similar.

The correct key, once found, should have a name which is a string of hex characters - this is one of the GUIDs corresponding to the .NET Core program. You can then use the following code to allow the installer to search for the presence of this key:

<util:RegistrySearch Id="VCRedistTest32" Root="HKLM" Key="SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall\{YOUR_GUID_HERE}" Result="exists" Variable="DOTNETPresent" Win64="no"/>

(Use Win64="yes" instead for the 64-bit registry)

You can then use the following for the ExePackage:

<ExePackage InstallCommand="/q" Id = "DotNetCore.Setup" SourceFile="..\DotNetCore\DotNetCore.exe" DetectCondition="DOTNETPresent"/>

Don't forget to add the reference to the util extension to the top-level wix element:

<Wix xmlns="http://schemas.microsoft.com/wix/2006/wi"
 xmlns:util="http://schemas.microsoft.com/wix/UtilExtension">

Answer 2

You need to use DetectCondition attribute and registry search that assign property in case the .net Core is installed.

ExePackage Element - DetectCondition

"A condition that determines if the package is present on the target system. This condition can use built-in variables and variables returned by searches. This condition is necessary because Windows doesn't provide a method to detect the presence of an ExePackage. Burn uses this condition to determine how to treat this package during a bundle action; for example, if this condition is false or omitted and the bundle is being installed, Burn will install this package."