If you attempt to create a user in SQL Server and get the following error:

You can only create a user with a password in a contained database

You probably didn’t quite configure your database as you intended. You can use the script below to fix it up (substitute DatabaseNameHere with your actual database name.

EXEC sp_configure 'contained database authentication', 1
GO

RECONFIGURE
GO

ALTER DATABASE DatabaseNameHere
SET containment = PARTIAL
GO