Powershell: Check for elevated permissions

Test-IsInElevatedMode.ps1

# Check whether we are running in elevated mode
function Test-IsInElevatedMode {
    <#
        .DESCRIPTION
        Checks to see whether the current Powershell prompt is running in elevated mode

        .EXAMPLE
        Test-IsInElevatedMode

        .OUTPUTS
        Returns $true when running in elevated mode, otherwise $false
    #>

    $requiredRole = [System.Security.Principal.WindowsBuiltInRole]::Administrator
    $identity = [System.Security.Principal.WindowsIdentity]::GetCurrent()
    $principal = New-Object System.Security.Principal.WindowsPrincipal($identity)

    if($principal.IsInRole($requiredRole) -eq $false){    
        Write-Warning "This script requires elevated permissions to execute. Please run the Powershell console as Administrator."
        exit
    }
}