Find MSI Uninstall ID.ps1

## Usage, Add the folowing function to your code.
##
## $process = Get-ProgramUninstallString -Filter "Application Name"
## $process.name
## $process.version
## $process.guid

function Get-ProgramUninstallString {
    [CmdletBinding(DefaultParameterSetName = "ByName")]
    [OutputType([PSCustomObject])]
    param (
        [Parameter(
            ParameterSetName = "ByName",
            ValueFromPipeline = $true,
            ValueFromPipelineByPropertyName = $true
        )]
        [Alias(
            "DisplayName"
        )]
        [String[]]
        $Name,
        [Parameter(
            ParameterSetName = "ByFilter"
        )]
        [String]
        $Filter = "*",
        [Parameter()]
        [Switch]
        $ShowNulls
    )
    begin {
        try {
            if (Test-Path -Path "HKLM:\SOFTWARE\WOW6432Node") {
                $programs = Get-ItemProperty -Path "HKLM:\SOFTWARE\WOW6432Node\Microsoft\Windows\CurrentVersion\Uninstall\*" -ErrorAction Stop
            }
            $programs += Get-ItemProperty -Path "HKLM:\SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall\*" -ErrorAction Stop
            $programs += Get-ItemProperty -Path "Registry::\HKEY_USERS\*\SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall\*" -ErrorAction SilentlyContinue
        } catch {
            Write-Error $_
            break
        }
    }
    process {
        if ($PSCmdlet.ParameterSetName -eq "ByName") {
            foreach ($nameValue in $Name) {
                $programs = $programs.Where({
                    $_.DisplayName -eq $nameValue
                })
            }
        } else {
            $programs = $programs.Where({
                $_.DisplayName -like "*$Filter*"
            })
        }

        if ($null -ne $programs) {
            if (-not ($ShowNulls.IsPresent)) {
                $programs = $programs.Where({
                    -not [String]::IsNullOrEmpty(
                        $_.UninstallString
                    )
                })
            }
            $output = $programs.ForEach({
                [PSCustomObject]@{
                    Name = $_.DisplayName
                    Version = $_.DisplayVersion
                    Guid = $_.PSChildName
                    UninstallString = $_.UninstallString
                }
            })
            Write-Output -InputObject $output
        }
    }
}