How to reset a Master Data Services service account password

Import-Module WebAdministration

$newUserName = "" # Domain\User
$newPassword = "" # Password

# You need to go through Sites to get to Pools
foreach ($site in (Get-ChildItem IIS:\Sites)) {
	foreach ($application in (Get-ChildItem $site.PSPath | Where { $_ -is [Microsoft.IIs.PowerShell.Framework.ConfigurationElement] })) {
		$globalPath = Join-Path $application.PhysicalPath Global.asax

		# Determine which pools are MDS ones
		if ((Test-Path $globalPath) -and (Get-Content $globalPath | Where { $_ -like "*Microsoft.MasterDataServices.WebUI.MDMGlobal*" })) {
			$poolPath = Join-Path "IIS:\AppPools" $application.applicationPool
			$pool = Get-Item $poolPath
			$mdsPoolName = $application.applicationPool

			$identityType = $pool.processModel.identityType
			$userName = $pool.processModel.userName
			$password = $pool.processModel.password

			"Application: $($application.Path)"
			"Pool:        $mdsPoolName"
			"             Auth $identityType, User $userName, Password $password"

			# IIS doesn't store password hashes, it stores the real thing :-(
			if ($userName -ne $newUserName -or $password -ne $newPassword) {
				# Set new username and password
				Set-ItemProperty IIS:\AppPools\$mdsPoolName -Name processModel -Value @{
				    userName = $newUserName
				    password = $newPassword
				    identityType = "SpecificUser"
				}

				# Restart this application pool (or start if it already failed due to a password expiry)
				if ((Get-WebAppPoolState $mdsPoolName).Value -eq "Started") {
				    Restart-WebAppPool $mdsPoolName
				    Start-Sleep -Seconds 1
				} else {
				    Start-WebAppPool $mdsPoolName
				}
			}

			# Test it's up, even if we didn't change anything
			try {
			    Invoke-WebRequest http://localhost$($application.Path)
			} catch {
				if ($_.Exception -like "*503*") { # HTTP Error 503. The service is unavailable.
					Write-Error "http://localhost$($application.Path) is no longer functioning and needs to be investigated."
			  	}
			}
		}
	}
}