New 25H2 Start Menu and Battery Icon...

#Requires -RunAsAdministrator
Add-Type -AssemblyName System.Windows.Forms
Add-Type -AssemblyName System.Drawing

# --- Registry helpers ---

function Get-OldStartEnabled {
    $path = "HKLM:\SYSTEM\ControlSet001\Control\FeatureManagement\Overrides\8\3036241548"

    if (Test-Path $path) {
        try {
            $state = Get-ItemPropertyValue -Path $path -Name EnabledState -ErrorAction SilentlyContinue
            if ($state -eq 1) { return $true }
        } catch {}
    }

    return $false
}

function Clear-FeatureManagementCache {
    $stores = @(
        'HKLM:\SYSTEM\ControlSet001\Control\FeatureManagement\Store',
        'HKLM:\SYSTEM\CurrentControlSet\Control\FeatureManagement\Store'
    )

    foreach ($s in $stores) {
        if (Test-Path $s) {
            Remove-Item $s -Recurse -Force -ErrorAction SilentlyContinue
        }
    }

    Stop-Service -Name "StateRepository" -Force -ErrorAction SilentlyContinue
    Start-Service -Name "StateRepository" -ErrorAction SilentlyContinue
}

function Set-OldStart {
    # Remove all override branches
    $branches = @('2','4','6','8','10','12','14')

    foreach ($branch in $branches) {
        $path = "HKLM:\SYSTEM\ControlSet001\Control\FeatureManagement\Overrides\$branch\3036241548"
        if (Test-Path $path) { Remove-Item $path -Recurse -Force -ErrorAction SilentlyContinue }
    }

    # Create parent key
    $parent = "HKLM:\SYSTEM\ControlSet001\Control\FeatureManagement\Overrides\8"
    if (-not (Test-Path $parent)) { New-Item -Path $parent -Force | Out-Null }

    # Create override key
    $override = "$parent\3036241548"
    if (-not (Test-Path $override)) { New-Item -Path $override -Force | Out-Null }

    # Apply values
    New-ItemProperty -Path $override -Name "EnabledState" -Value 1 -PropertyType DWord -Force | Out-Null
    New-ItemProperty -Path $override -Name "EnabledStateOptions" -Value 0 -PropertyType DWord -Force | Out-Null

    Clear-FeatureManagementCache
}

function Set-NewStart {
    # Remove override branches
    $branches = @('2','4','6','8','10','12','14')

    foreach ($branch in $branches) {
        $path = "HKLM:\SYSTEM\ControlSet001\Control\FeatureManagement\Overrides\$branch"
        if (Test-Path $path) { Remove-Item $path -Recurse -Force -ErrorAction SilentlyContinue }
    }

    # Create parent branch 14
    $parent = "HKLM:\SYSTEM\ControlSet001\Control\FeatureManagement\Overrides\14"
    if (-not (Test-Path $parent)) { New-Item -Path $parent -Force | Out-Null }

    # IDs from reg
    $ids = @(
        '156965516',
        '3036241548',
        '1853569164',
        '2792562829',
        '762256525',
        '734731404',
        '2114784909',
        '905601679'
    )

    foreach ($id in $ids) {
        $key = "$parent\$id"
        if (-not (Test-Path $key)) { New-Item -Path $key -Force | Out-Null }

        New-ItemProperty -Path $key -Name "EnabledState" -Value 2 -PropertyType DWord -Force | Out-Null
        New-ItemProperty -Path $key -Name "EnabledStateOptions" -Value 0 -PropertyType DWord -Force | Out-Null
    }

    Clear-FeatureManagementCache
}

# --- GUI ---

$form                  = New-Object System.Windows.Forms.Form
$form.Text             = "Start Menu Toggle"
$form.Size             = New-Object System.Drawing.Size(360,200)
$form.StartPosition    = "CenterScreen"
$form.FormBorderStyle  = "FixedDialog"
$form.MaximizeBox      = $false
$form.MinimizeBox      = $false

$label                 = New-Object System.Windows.Forms.Label
$label.Text            = "Choose Start menu style:"
$label.AutoSize        = $true
$label.Location        = New-Object System.Drawing.Point(20,20)
$form.Controls.Add($label)

$radioNew              = New-Object System.Windows.Forms.RadioButton
$radioNew.Text         = "New Start menu (Windows 11 default)"
$radioNew.AutoSize     = $true
$radioNew.Location     = New-Object System.Drawing.Point(40,50)
$form.Controls.Add($radioNew)

$radioOld              = New-Object System.Windows.Forms.RadioButton
$radioOld.Text         = "Old Start menu (override)"
$radioOld.AutoSize     = $true
$radioOld.Location     = New-Object System.Drawing.Point(40,80)
$form.Controls.Add($radioOld)

$buttonApply           = New-Object System.Windows.Forms.Button
$buttonApply.Text      = "Apply"
$buttonApply.Size      = New-Object System.Drawing.Size(80,30)
$buttonApply.Location  = New-Object System.Drawing.Point(80,120)
$form.Controls.Add($buttonApply)

$buttonCancel          = New-Object System.Windows.Forms.Button
$buttonCancel.Text     = "Cancel"
$buttonCancel.Size     = New-Object System.Drawing.Size(80,30)
$buttonCancel.Location = New-Object System.Drawing.Point(180,120)
$form.Controls.Add($buttonCancel)

# Pre-select based on current state
if (Get-OldStartEnabled) {
    $radioOld.Checked = $true
} else {
    $radioNew.Checked = $true
}

$buttonApply.Add_Click({
    if (-not $radioNew.Checked -and -not $radioOld.Checked) {
        [System.Windows.Forms.MessageBox]::Show(
            "Select New or Old Start menu first.",
            "Start Menu Toggle",
            [System.Windows.Forms.MessageBoxButtons]::OK,
            [System.Windows.Forms.MessageBoxIcon]::Warning
        ) | Out-Null
        return
    }

    try {
        if ($radioOld.Checked) {
            Set-OldStart
        } else {
            Set-NewStart
        }
    } catch {
        [System.Windows.Forms.MessageBox]::Show(
            "Failed to write registry. Run as Administrator.",
            "Error",
            [System.Windows.Forms.MessageBoxButtons]::OK,
            [System.Windows.Forms.MessageBoxIcon]::Error
        ) | Out-Null
        return
    }

    $result = [System.Windows.Forms.MessageBox]::Show(
        "Changes applied. A reboot is required for the Start menu to switch.`nReboot now?",
        "Reboot required",
        [System.Windows.Forms.MessageBoxButtons]::YesNo,
        [System.Windows.Forms.MessageBoxIcon]::Question
    )

    if ($result -eq [System.Windows.Forms.DialogResult]::Yes) {
        $form.Close()
        Restart-Computer -Force
    } else {
        $form.Close()
    }
})

$buttonCancel.Add_Click({
    $form.Close()
})

[void]$form.ShowDialog()