This was a stupid one.
Use SSMS to check if the MSSQL instance is configure to allow logging in using only Windows Authentication.
Switch to both SQL Server Authentication and Windows Authentication and restart the service.
Bruce Ng's software development blog
An archive of solutions of programming problems I have faced in my career
This was a stupid one.
Use SSMS to check if the MSSQL instance is configure to allow logging in using only Windows Authentication.
Switch to both SQL Server Authentication and Windows Authentication and restart the service.