Windows Installer PowerShell Snap-In – Getting MSI data via PowerShell

CodePlex - Windows Installer PowerShell Snap-In

“…Windows Installer snap-in provides cmdlets ("command-lets") - similar to functions - to query package states, patches registered and applied to products, and more.

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Windows Installer PowerShell Snap-In - Help (v1)

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Cmdlets

• Get-MSIFileHash
• Get-MSIFileType
• Get-MSIPatchInfo
• Get-MSIProductInfo
• Get-MSIRelatedProductInfo
• Get-MSISource

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v2 is on the way, with PowerShell v2 support (the PSMSI v2 Alpha was just released)