Powershell - Add Permanent Environment variable

These are the two PowerShell commands you need to permanently update the Path environment variable Start as ADMIN.

PS C:\Users\donald> Set-ItemProperty -Path 'Registry::HKEY_LOCAL_MACHINE\System\CurrentControlSet\Control\Session Manager\Environment' -Name PATH -Value ($Old_Path += ';z:\Dropbox\prio\')

PS C:\Users\donald> Get-Item Env:Path|fl