1) USE [master]
GO
ALTER LOGIN [sa] WITH DEFAULT_DATABASE=[master],
DEFAULT_LANGUAGE=[us_english], CHECK_EXPIRATION=ON, CHECK_POLICY=ON
GO
USE [master]
GO
ALTER LOGIN [sa] WITH PASSWORD=N'yeni_sifre' MUST_CHANGE
GO
2) start > run > cmd...
OSQL -S
1> EXEC sp_password NULL, '
2> GO