Difference between the Windows User Name Format in Domain and Workgroup?

Question

On Windows Domain I know the default user name format is domain\username. But on workgroup I ma little confused. For example, running a .NET application on development server gives me, my app is running under computer-name\myname user and running same app on IIS gives me IIS APPPOOL\ASP.NET v4.0. So, how should I read this format?

Answer 1

The part before the backslash can be one of three things:

1. The domain name
2. The computer name if not in a domain or using local accounts even if in a domain. The workgroup name is never used in account names.
3. A special account type (I don't know whether there is an offical name for this). There are a few different of these types, old ones are BUILTIN and 'NT AUTHORITY' for internal Windows accounts. Newer ones are 'NT SERVICE' and 'IIS APPPOOL', these are pseudo accounts that like the internal ones (system, NetworkService etc) have no passwords, but you can add them to groups and can assign permissions to them. Still you wont see them showing up in any list of Windows accounts.

'NT SERVICE\myservicename' is used to run a Windows service under a unique account, same with 'IIS APPPOOL\AppPoolName' which is used to run a single IIS application pool and separate its permission from any other pools. You have to type them in.

So your app is running under two different user accounts, that's all.