This account is used by IIS to run out-of-process applications .If installed on a domain controller, this account is added to the Domain Users and IIS_WPG groups. When IIS is installed on a member server, it is only a member of the IIS_WPG group.
The Launch IIS Process account is automatically created by IIS. The account is a local account if IIS is installed on member servers and a domain account if IIS is installed on a domain controller. It is also stored in the IIS metabase.