1612 - The installation source for this product is not available. Verify that the source exists and that you can access it. Error 1612 may be produced during a repair or uninstall of a Windows Installer product. In some environments, files in the '$

Get-WILocalPackages.ps1

#region Get-WILocalPackages
function Get-WILocalPackages {
    [CmdletBinding()]
    PARAM(
        [Parameter(Mandatory = $false)]
        [switch]
        $Audit
        ,
        [Parameter(Mandatory = $false)]
        [string[]]
        $ComputerName = $env:COMPUTERNAME
    )

    begin {
        Write-Verbose $MyInvocation.MyCommand
        Write-Verbose "ComputerName: $ComputerName"
    }

    process {
        foreach ($ComputerNameEx In $ComputerName) {
            try {
                $Properties = @{
                    ComputerName = $ComputerNameEx
                    Found      = $null
                    NotFound   = $null
                    FoundSize  = $null
                    FolderSize = $null
                }
                try {

                    if (@('.', 'localhost', $env:COMPUTERNAME) -notcontains $Properties.ComputerName) {
                        Write-Verbose "Remote computer"
                        $key = [Microsoft.Win32.RegistryKey]::OpenRemoteBaseKey('LocalMachine', $Properties.ComputerName)
                    }
                    else {
                        Write-Verbose "Local computer"
                        $key = [Microsoft.Win32.Registry]::LocalMachine
                    }

                    $LocalPackages = @()

                    $Products = $key.OpenSubKey('SOFTWARE\Microsoft\Windows\CurrentVersion\Installer\UserData\S-1-5-18\Products', $false)

                    $LocalPackages += ForEach ($SubKeyName In $Products.GetSubKeyNames()) {
                        try {
                            $subkey = $Products.OpenSubKey($SubKeyName)
                            $InstallProperties = $subkey.OpenSubKey('InstallProperties')
                            $InstallProperties.GetValue('LocalPackage') | Select-Object -Property @{Name="LocalPackage";Expression={$_}}
                        }
                        catch {
                        }
                    }

                    $Patches = $key.OpenSubKey('SOFTWARE\Microsoft\Windows\CurrentVersion\Installer\UserData\S-1-5-18\Patches', $false)
                    $LocalPackages += ForEach ($SubKeyName In $Patches.GetSubKeyNames()) {
                        try {
                            $subkey = $Products.OpenSubKey($SubKeyName)
                            $subkey.GetValue('LocalPackage') | Select-Object -Property @{Name = "LocalPackage"; Expression = {$_}}
                        }
                        catch {
                        }
                    }

                    $LocalPackages = $LocalPackages | Where-Object { $_.LocalPackage } | ForEach-Object {
                        if (@('.', 'localhost', $env:COMPUTERNAME) -notcontains $Properties.ComputerName) {
                            $_.LocalPackage = "\\$($Properties.ComputerName)\$($_.LocalPackage -replace ':', '$')"
                            $_
                        }
                        else {
                            $_
                        }
                    }

                    $LocalPackages | ForEach-Object {
                        $_ | Add-Member -MemberType NoteProperty -Name "FileExist" -Value (Test-Path -Path $_.LocalPackage -PathType Leaf)
                        $_ | Add-Member -MemberType NoteProperty -Name "Length" -Value ((Get-Item -Path $_.LocalPackage -ErrorAction SilentlyContinue).Length)
                    }
                    $Properties.Found = ($LocalPackages | Where-Object { $_.FileExist -eq $true } | Measure-Object).Count
                    $Properties.NotFound = ($LocalPackages | Where-Object { $_.FileExist -eq $false } | Measure-Object).Count
                    $Properties.FoundSize = ($LocalPackages | Measure-Object -Sum Length | Select-Object -ExpandProperty Sum)
                    if (@('.', 'localhost', $env:COMPUTERNAME) -notcontains $Properties.ComputerName) {
                        $System32 = (Get-CimInstance -ClassName Win32_OperatingSystem -ComputerName $Properties.ComputerName).SystemDirectory
                        $Windir = Split-Path -Path $System32
                        $InstallerDir = Join-Path -Path $Windir -ChildPath "Installer"
                        $RemoteInstallerDir = $InstallerDir -replace ':', '$'
                        $Path = "\\$($Properties.ComputerName)\$($RemoteInstallerDir)"
                        Write-Verbose "Remote Installer Directory: $Path"
                        $Properties.FolderSize = (Get-ChildItem -Path $Path -Force | Measure-Object -Sum Length | Select-Object -ExpandProperty Sum)
                    }
                    else {
                        $Properties.FolderSize = (Get-ChildItem -Path $env:WINDIR\Installer -Force | Measure-Object -Sum Length | Select-Object -ExpandProperty Sum)
                    }

                }
                catch {
                    Write-Verbose $_.Exception.Message
                }

                if ($Audit) {
                    $obj = New-Object -TypeName PSObject -Property $Properties
                    Write-Output -InputObject $obj
                }
                else {
                    $LocalPackages
                }
            }
            catch {
                Throw $_
            }
        }
    }

    end {
    }
}
#endregion Get-WILocalPackages