SQL Server Analysis Services Account Name is missing

I'm trying to install SQL Server 2012 on Windows Server 2012, but when I get to: enter image description here

The SQL Server Analysis Services are empty so I can't continue instalation proces. Any idea what Account Name should be there? And how to add it?

How do I find SQL Server service account?

To retrieve the service account of current SQL Server installation from the registry, log into SQL Server Management Studio and run the attached SQL script (FindSQLServiceACCT. sql). Another method is to query sys. dm_server_services view.

How do I give someone admin access to SSAS?

Launch Microsoft SQL Server Management Studio on the server that runs the SQL Server Analysis Services (SSAS). Navigate to Databases >[SIS/CRM Semantic Model name] > Roles. The Administrators and ReadOnly roles are created by default. Add users to these roles as required.

Not sure why a default is missing, but this is a service account, so as with any other service account, best practice is to create a user in AD for this purpose only and to assign this user account (making sure it has sufficient permissions on the local machine where SSAS is running) to the SSAS service on installation.