Get Windows 7 Product Key Powershell

I'm trying to write up a health report to more easily see an overview of all pcs under my control.

This is what i have so far:

$ErrorActionPreference = "silentlycontinue"
$ComputerList = get-content C:\Users\Administrator\Desktop\DavidsScripts\FloorHealth\input.txt
$collectionVariable = New-Object System.Collections.ArrayList

ForEach ($Computer in $ComputerList) {
# Create temp object
$temp = New-Object System.Object
# Add members to temp object

$temp | Add-Member -MemberType NoteProperty -Name "Keys" (Get-WmiObject -query ‘select * from 
SoftwareLicensingService’).OA3xOriginalProductKey
$temp | Add-Member -MemberType NoteProperty -Name "PC" (Get-WMIObject -ComputerName $Computer 
Win32_ComputerSystem | Select-Object -ExpandProperty name)
$temp | Add-Member -MemberType NoteProperty -Name "IP" -Value $Computer
$temp | Add-Member -MemberType NoteProperty -Name "MACAddress" -Value (gwmi -ComputerName $Computer 
-Class Win32_NetworkAdapterConfiguration | where {$_.IPAddress -like "$Computer"}).MACAddress
$temp | Add-Member -MemberType NoteProperty -Name "Ram" (Get-WMIObject -class Win32_PhysicalMemory - 
ComputerName $Computer | Measure-Object -Property capacity -Sum | % {[Math]::Round(($_.sum / 
1GB),2)})
$temp | Add-Member -MemberType NoteProperty -Name "Firewall" -Value ((netsh -r $Computer advfirewall 
show currentprofile state)[3] -replace 'State' -replace '\s')
# Add the temp object to ArrayList
$collectionVariable.Add($temp)
}

Write-Output $collectionVariable
$collectionVariable | Export-Excel -now 
C:\Users\Administrator\Desktop\DavidsScripts\FloorHealth\floorhealth.xlsx

Im Having a hard time trying to get the windows Product Key. (sorry about the formatting on the first 1 couldn't keep the longer lines on there own line)

I wrote up a second script but not quite sure how to add it to my existing without just pasting the code into it. Can i call it and run the script from inside my health report then split out just the product key, then send it into excel?

($targets = get-content C:\Users\Administrator\Desktop\DavidsScripts\FloorHealth\input.txt)
$hklm = 2147483650
$regPath = "Software\Microsoft\Windows NT\CurrentVersion"
$regValue = "DigitalProductId"
Foreach ($target in $targets) {
    $productKey = $null
    $win32os = $null
    $wmi = [WMIClass]"\\$target\root\default:stdRegProv"
    $data = $wmi.GetBinaryValue($hklm,$regPath,$regValue)
    $binArray = ($data.uValue)[52..66]
    $charsArray = 
"B","C","D","F","G","H","J","K","M","P","Q","R","T","V","W","X","Y","2","3","4","6","7","8","9"
    ## decrypt base24 encoded binary data
    For ($i = 24; $i -ge 0; $i--) {
        $k = 0
        For ($j = 14; $j -ge 0; $j--) {
            $k = $k * 256 -bxor $binArray[$j]
            $binArray[$j] = [math]::truncate($k / 24)
            $k = $k % 24
        }
        $productKey = $charsArray[$k] + $productKey
        If (($i % 5 -eq 0) -and ($i -ne 0)) {
            $productKey = "-" + $productKey
        }
    }
    $obj = New-Object Object
    $obj | Add-Member Noteproperty ProductKey -value $productkey
    $obj
}

First of all I would split things up, so it's more clear what function is doing what job. The advantage of using Functions is that you don't need a separate script file for each functionality.

Something like this:

Function Get-WindowsProductKey {
    Param (
        [String[]]$ComputerName = $env:COMPUTERNAME
    )

    Function Convert-ProductKey {
        Param (
            [Parameter(Mandatory)]
            [String[]]$DigitialProductID,
            [String[]]$charsArray = @(
                "B", "C", "D", "F", "G", "H", "J", "K", "M",
                "P", "Q", "R", "T", "V", "W", "X", "Y", "2",
                "3", "4", "6", "7", "8", "9"
            )
        )
        ## decrypt base24 encoded binary data
        For ($i = 24; $i -ge 0; $i--) {
            $k = 0
            For ($j = 14; $j -ge 0; $j--) {
                $k = $k * 256 -bxor $DigitialProductID[$j]
                $DigitialProductID[$j] = [math]::truncate($k / 24)
                $k = $k % 24
            }
            $productKey = $charsArray[$k] + $productKey
            If (($i % 5 -eq 0) -and ($i -ne 0)) {
                $productKey = "-" + $productKey
            }
        }

        $productKey
    }

    Function Get-DigitalProductID {
        Param (
            [Parameter(Mandatory)]
            [String]$ComputerName,
            $hklm = 2147483650,
            $regPath = "Software\Microsoft\Windows NT\CurrentVersion",
            $regValue = "DigitalProductId"
        )

        $wmi = [WMIClass]"\\$C\root\default:stdRegProv"
        $data = $wmi.GetBinaryValue($hklm, $regPath, $regValue)
        ($data.uValue)[52..66]
    }

    Foreach ($C in $ComputerName) {
        $DigitalProductID = Get-DigitalProductID -ComputerName $C
        $ProductKey = Convert-ProductKey -DigitialProductID $DigitalProductID

        [PSCustomObject]@{
            ComputerName = $C
            ProductKey   = $ProductKey
        }
    }
}

Function Get-ComputerDetail {
    Param (
        [String[]]$ComputerName = $env:COMPUTERNAME
    )

    ForEach ($C in $ComputerName) {
        $Mac = (Get-WMIObject -ComputerName $C -Class 'Win32_NetworkAdapterConfiguration' | Where-Object { $_.IPAddress -like "$C" }).MACAddress

        $Ram = (Get-WMIObject  -ComputerName $C -class 'Win32_PhysicalMemory' |
            Measure-Object -Property capacity -Sum |
            ForEach-Object { [Math]::Round(($_.sum / 1GB), 2) })

        $Firewall = ((netsh -r $C advfirewall show currentprofile state)[3] -replace 'State' -replace '\s')

        $Keys = (Get-WmiObject -ComputerName $C -Query 'select * from SoftwareLicensingService').OA3xOriginalProductKey

        [PSCustomObject]@{
            ComputerName      = (Get-WMIObject -ComputerName $C -class  'Win32_ComputerSystem').Name
            IP                = $C
            Keys              = $Keys
            MACAddress        = $Mac
            RAM               = $Ram
            Firewall          = $Firewall
            WindowsProductKey = Get-WindowsProductKey -ComputerName $C
        }
    }
}

$ComputerNames =  Get-Content -Path 'C:\Users\Administrator\Desktop\DavidsScripts\FloorHealth\input.txt)'
$ComputerDetails = Get-ComputerDetail -ComputerName $ComputerNames
$ComputerDetails | Export-Excel -Now