Windows Username to SID mapping
I needed to map the sids of some users to their usernames the other day so I though that I should be able to use WMI to do it. Indeed, you can use the command wmic useraccount get name,sid that will output a list of usernames and their sids. If you try to run this on Powershell you'll get an error message about invalid GET expression, that is because of the comma. You can use the Start-Process cmdlet and start the command with the necessary arguments.