The information in this article applies to PowerShell tasks, which were introduced in Prism Deploy 16.0.

When creating a PowerShell Task in Prism Deploy, you have the option to choose the minimum version of PowerShell that's required to run the Task. If you use this option, the version you choose becomes a prerequisite on the Task. If the target system doesn't meet the prerequisite, the Task won't attempt to run.

The latest version of the PowerShell core (as of 2/1/2017) is version 5. Each Windows operating system has a default version of the PowerShell core installed. The default versions per operating system are shown below. Note: Powershell 1.0 is not supported for Prism's PowerShell Tasks.

PowerShell version 5 can be installed side by side with version 2. PowerShell versions 3 and 4 can be upgraded to version 5.

Each version of the PowerShell core is forward-compatible. This means any script or cmdlet that worked in an earlier version should still work in later versions. However, the PowerShell core and the Windows operating system interact to determine what commands and cmdlets will work. For example, cmdlets that are available on Windows 10 are not available on Windows 7. Likewise, server operating systems have many cmdlets that workstation operating systems don’t. So even if you update the PowerShell core, you won’t get the cmdlets from newer operating systems.

More information about PowerShell versions and related topics is available on Microsoft's Hey! Scripting Guy blog.