Gets the current software update level of a Windows 10/11 workstation and compares with the latest available updates. Can also list all available updates for the current build.

Get-CurrentPatchInfo.ps1

[CmdletBinding()]
Param(
    [switch]$ListAllAvailable,
    [switch]$ExcludePreview,
    [switch]$ExcludeOutofBand
)
$ProgressPreference = 'SilentlyContinue'

Function Get-MyWindowsVersion {
    [CmdletBinding()]
    Param
    (
        $ComputerName = $env:COMPUTERNAME
    )

    $Table = New-Object System.Data.DataTable
    $Table.Columns.AddRange(@("ComputerName","Windows edition","Version","Build number"))
    $ProductName = Get-CimInstance -ClassName Win32_OperatingSystem -Property Caption | Select -ExpandProperty Caption
    Try
    {
        $DisplayVersion = (Get-ItemPropertyValue 'HKLM:\SOFTWARE\Microsoft\Windows NT\CurrentVersion' -Name DisplayVersion -ErrorAction Stop)
    }
    Catch
    {
        $DisplayVersion = "N/A"
    }
    $CurrentBuild = Get-ItemPropertyValue 'HKLM:\SOFTWARE\Microsoft\Windows NT\CurrentVersion' -Name CurrentBuild
    $UBR = Get-ItemPropertyValue 'HKLM:\SOFTWARE\Microsoft\Windows NT\CurrentVersion' -Name UBR
    $OSVersion = $CurrentBuild + "." + $UBR
    $TempTable = New-Object System.Data.DataTable
    $TempTable.Columns.AddRange(@("ComputerName","Windows edition","Version","Build number"))
    [void]$TempTable.Rows.Add($env:COMPUTERNAME,$ProductName,$DisplayVersion,$OSVersion)

    Return $TempTable
}

Function Convert-ParsedArray {
    Param($Array)
    
    $ArrayList = New-Object System.Collections.ArrayList
    foreach ($item in $Array)
    {      
        [void]$ArrayList.Add([PSCustomObject]@{
            Update = $item.outerHTML.Split('>')[1].Replace('</a','').Replace('&#x2014;',' - ')
            KB = "KB" + $item.href.Split('/')[-1]
            InfoURL = "https://support.microsoft.com" + $item.href
            OSBuild = [int]$item.outerHTML.Split('.')[-1].Split(')')[0] # Just for sorting
        })
    }
    Return $ArrayList
}

# Get Windows info
$CurrentWindowsVersion = Get-MyWindowsVersion -ErrorAction Stop

# Set the correct URL for W11 or W10
If ($CurrentWindowsVersion.'Build number' -like "2*")
{
    $URI = "https://aka.ms/Windows11UpdateHistory"
}
If ($CurrentWindowsVersion.'Build number' -like "1*")
{
    $URI = "https://support.microsoft.com/en-gb/topic/windows-10-update-history-7dd3071a-3906-fa2c-c342-f7f86728a6e3"
}

# Retrieve the web pages
If ($PSVersionTable.PSVersion.Major -ge 6)
{
    $Response = Invoke-WebRequest -Uri $URI -ErrorAction Stop
}
else 
{
    $Response = Invoke-WebRequest -Uri $URI -UseBasicParsing -ErrorAction Stop
}
    
# Pull the version data from the HTML
If (!($Response.Links))
{ throw "Response was not parsed as HTML"}
$VersionDataRaw = $Response.Links | where {$_.outerHTML -match "supLeftNavLink" -and $_.outerHTML -match "KB"}

# Pull all the update info if requested
If ($ListAllAvailable)
{
    If ($ExcludePreview -and $ExcludeOutofBand)
    {
        $AllAvailable = $VersionDataRaw | where {$_.outerHTML -match $CurrentWindowsVersion.'Build number'.Split('.')[0] -and $_.outerHTML -notmatch "Preview" -and $_.outerHTML -notmatch "Out-of-band"}
    }
    ElseIf ($ExcludePreview)
    {
        $AllAvailable = $VersionDataRaw | where {$_.outerHTML -match $CurrentWindowsVersion.'Build number'.Split('.')[0] -and $_.outerHTML -notmatch "Preview"}
    }
    ElseIf ($ExcludeOutofBand)
    {
        $AllAvailable = $VersionDataRaw | where {$_.outerHTML -match $CurrentWindowsVersion.'Build number'.Split('.')[0] -and $_.outerHTML -notmatch "Out-of-band"}
    }
    Else
    {
        $AllAvailable = $VersionDataRaw | where {$_.outerHTML -match $CurrentWindowsVersion.'Build number'.Split('.')[0]}
    }
    $UniqueList = (Convert-ParsedArray -Array $AllAvailable) | Select -Property * -Unique | Sort OSBuild -Descending 
    $Table = New-Object System.Data.DataTable
    [void]$Table.Columns.AddRange(@('Update','KB','InfoURL'))
    foreach ($Update in $UniqueList)
    {
        [void]$Table.Rows.Add(
            $Update.Update,
            $Update.KB,
            $Update.InfoURL
        )
    }
    Return $Table
}

# Get the latest patch info
$CurrentPatch = $VersionDataRaw | where {$_.outerHTML -match $CurrentWindowsVersion.'Build number'} | Select -First 1
If ($ExcludePreview -and $ExcludeOutofBand)
{
    $LatestAvailablePatch = $VersionDataRaw | where {$_.outerHTML -match $CurrentWindowsVersion.'Build number'.Split('.')[0] -and $_.outerHTML -notmatch "Out-of-band" -and $_.outerHTML -notmatch "Preview"} | Select -First 1
}
ElseIf ($ExcludePreview)
{
    $LatestAvailablePatch = $VersionDataRaw | where {$_.outerHTML -match $CurrentWindowsVersion.'Build number'.Split('.')[0] -and $_.outerHTML -notmatch "Preview"} | Select -First 1
}
ElseIf ($ExcludeOutofBand)
{
    $LatestAvailablePatch = $VersionDataRaw | where {$_.outerHTML -match $CurrentWindowsVersion.'Build number'.Split('.')[0] -and $_.outerHTML -notmatch "Out-of-band"} | Select -First 1
}
Else
{
    $LatestAvailablePatch = $VersionDataRaw | where {$_.outerHTML -match $CurrentWindowsVersion.'Build number'.Split('.')[0]} | Select -First 1
}
    
# Add the data to a table
$Table = New-Object System.Data.DataTable
[void]$Table.Columns.AddRange(@('OSVersion','OSEdition','OSBuild','CurrentInstalledUpdate','CurrentInstalledUpdateKB','CurrentInstalledUpdateInfoURL','LatestAvailableUpdate','LastestAvailableUpdateKB','LastestAvailableUpdateInfoURL'))
[void]$Table.Rows.Add(
    $CurrentWindowsVersion.Version,
    $CurrentWindowsVersion.'Windows edition',
    $CurrentWindowsVersion.'Build number',
    $CurrentPatch.outerHTML.Split('>')[1].Replace('</a','').Replace('&#x2014;',' - '),
    "KB" + $CurrentPatch.href.Split('/')[-1],
    "https://support.microsoft.com" + $CurrentPatch.href,
    $LatestAvailablePatch.outerHTML.Split('>')[1].Replace('</a','').Replace('&#x2014;',' - '),
    "KB" + $LatestAvailablePatch.href.Split('/')[-1],
    "https://support.microsoft.com" + $LatestAvailablePatch.href
    )
Return $Table

Hi, I got an error when running the cmdlet:

PS C:\Users\sicopadmin\workspaces\powershell> .\Get-CurrentPatchInfo -ExcludePreview -ExcludeOutofBand InvalidOperation: C:\Users\sicopadmin\workspaces\powershell\Get-CurrentPatchInfo.ps1:121 Line | 121 | [void]$Table.Rows.Add( | ~~~~~~~~~~~~~~~~~~~~~~ | You cannot call a method on a null-valued expression. PS C:\Users\sicopadmin\workspaces\powershell>

Any advice on how to fix this error from happen again?

same here. @ejespino1127 were you able to fix it?