Alternate Access Mappings and Windows Powershell

I had a request this week on how to leverage Windows Powershell to add Alternate Access Mappings to the collection for a specific Web application.  Surprisingly after some searching I was unable to find anything existing on the topic, so for those curious see the attached script and corresponding source Xml.


  1. Copy the source below into somefile.ps1.
  2. Copy the Xml source in AAM.xml.
  3. In the Windows Powershell console call ./somefile.ps1.


# Function:    main
# Description:    Main entry point for the script.  Loads the configuration source
#        Xml and initializes the foreach loop to iterate over a
#         collection of Xml nodes.
# Parameters:    None

function main()
  [xml]$cfg = Get-Content .AAM.xml

  if( $? -eq $false ) {
    Write-Host "Cannot load configuration source Xml $cfg."
    return $false

  $cfg.Configuration.WebApplication | ForEach-Object {
    new-SPAlternateUrl( $_ )

# Function:     New-SPAlternateURL
# Description:     This script adds the specified URLs to the collection of
#        alternate request URLs for the Web application.
# Parameters:    None

function New-SPAlternateURL( [object] $cfg )

  $webApp = $nul;
  $webApp = [Microsoft.SharePoint.Administration.SPWebApplication]::Lookup($cfg.Url)
  trap [Exception] { 
    Write-Error $("Exception: " + $_.Exception.Message);

  $cfg.AlternateUrl | ForEach-Object {
  $map=New-Object Microsoft.SharePoint.Administration.SPAlternateUrl($_.IncomingUrl, $_.UrlZone)
  return $map


Source Xml

<?xml version="1.0" encoding="utf-8"?>
  <WebApplication Url="http://contoso">
    <AlternateUrl IncomingUrl="" UrlZone="Internet" />
    <AlternateUrl IncomingUrl="http://contoso:1234" UrlZone="Custom" />
    <AlternateUrl IncomingUrl="http://contoso:4321" UrlZone="Custom" />