Custom Inventory for Intune: Creates fake software inventory entries (Add Remove Programs / Installed Apps) used to create custom inventory items in Intune

New-IntuneInvEntry.ps1

Function New-IntuneInvEntry {
    <#
    .SYNOPSIS
        Creates fake software inventory entries (Add Remove Programs / Installed Apps)
        used to create custom inventory items in Intune
    .DESCRIPTION
        Creates fake software inventory entries in HKLM|HKCU:\SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall
        with the DisplayName, DisplayVersion, Publisher, InstallDate, NoModify, NoRepair, NoRemove. If it should
        be hidden in Add/Remove Programs and Installed Apps it will also set the SystemComponent and WindowsInstaller values to 1.

        The Intune Management Extension will read these entries and report them as software inventory. 
        This can be used to create custom inventory items in Intune 
    .PARAMETER Prefix
        The prefix of the registry key. Default is IntuneInv
    .PARAMETER Separator
        The separator between the prefix and the name. Default is :
    .PARAMETER Publisher
        The publisher of the registry key. Default is the prefix
    .PARAMETER Name
        The name of the registry key. This will be used as the DisplayName
    .PARAMETER Value
        The value of the registry key. This will be used as the DisplayVersion
    .PARAMETER ShowInAddRemovePrograms
        If this switch is present the registry key will be visible in Add/Remove Programs
    .PARAMETER RunAsUser
        If this switch is present the registry key will be created 
        in HKCU:\SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall
    .EXAMPLE
        New-IntuneInvEntry -Name "Visible" -Value "ShowInAddRemove" -ShowInAddRemovePrograms
    .EXAMPLE
        New-IntuneInvEntry -Name "Hidden" -Value "HideInAddRemove"
    .EXAMPLE
        New-IntuneInvEntry -Name "SomeUserValue" -Value "SomeValue" -RunAsUser
    .EXAMPLE
        New-IntuneInvEntry -Name "SomeUserValueVisible" -Value "SomeValue" -RunAsUser -ShowInAddRemovePrograms -Verbose
    .NOTES
        Author: Marius Wyss
        Date: 2023-10-5
        Website: https://ittips.ch
        Twitter: @MrWyss-MSFT
        GitHub: https://github.com/MrWyss-MSFT
    #>
    [CmdletBinding()]
    param (
        [Parameter(Mandatory = $false)] [ValidateLength(1,15)] [String] $Prefix = "IntuneInv",
        [Parameter(Mandatory = $false)] [ValidateLength(1,1)] [String] $Separator = ":",
        [Parameter(Mandatory = $false)] [ValidateLength(1,64)] [String] $Publisher = $Prefix,
        [Parameter(Mandatory = $true)]  [ValidateLength(1,48)] [String] $Name,
        [Parameter(Mandatory = $true)]  [ValidateLength(1,64)] [String] $Value,
        [Parameter(Mandatory = $false)] [Switch] $ShowInAddRemovePrograms,
        [Parameter(Mandatory = $false)] [switch] $RunAsUser
    )

    # Set the registry path, if the RunAsUser switch is present use HKCU, else HKLM
    $RegPath = "{0}:\SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall" -f $(if ($RunAsUser.IsPresent) {"HKCU"} else {"HKLM"})

    # Prepare Vars
    $KeyName = "$Prefix$Separator$Name"
    $RegDate = (Get-Date).ToString("yyyyMMdd")

    Write-Verbose -Message "----------------- Creating Registry Key -----------------"
    # Create a new Registry key
    $RegKey = New-Item -Path $RegPath -Name $KeyName -Force
    Write-Verbose -Message "Created Registry Key: $KeyName in $RegPath"

    # Set the value of the registry key
    # DisplayName as Variable Name
    $RegKey | Set-ItemProperty -Name "DisplayName" -Value $KeyName -Force
    Write-Verbose -Message "Set DisplayName to $KeyName"
    
    # DisplayVersion as Variable Value
    $RegKey | Set-ItemProperty -Name "DisplayVersion" -Value $Value -Force
    Write-Verbose -Message "Set DisplayVersion to $Value"
    
    # Publisher to the Prefix
    $RegKey | Set-ItemProperty -Name "Publisher" -Value $Publisher -Force
    Write-Verbose -Message "Set Publisher to $Publisher"
   
    # Set InstallDate in the yyyymmdd format
    $RegKey | Set-ItemProperty -Name "InstallDate" -Value $RegDate -Force
    Write-Verbose -Message "Set InstallDate to $RegDate"
            
    # Set NoModify, NoRepair, NoRemove for Add/Remove Programs
    $RegKey | Set-ItemProperty -Name "NoModify" -Value 1 -Force
    $RegKey | Set-ItemProperty -Name "NoRepair" -Value 1 -Force
    $RegKey | Set-ItemProperty -Name "NoRemove" -Value 1 -Force
    Write-Verbose -Message "Set NoModify, NoRepair, NoRemove to 1"

    # Hide the entry in Add/Remove Programs and Installed Apps
    if (-not $ShowInAddRemovePrograms.IsPresent) {
        $RegKey | Set-ItemProperty -Name "SystemComponent " -Value 1 -Force
        $Regkey | Set-ItemProperty -Name "WindowsInstaller" -Value 1 -Force
        Write-Verbose -Message "Set SystemComponent and WindowsInstaller to 1"
    }
    Write-Verbose -Message "---------------------------------------------------------"
    Write-Verbose -Message ""
}