Connection String not connecting
Microsoft SQL Server Express installations
Most connection issues for MS SQL Server Express installation are caused by a spelling error or a problem with the SQL user’s setup.
Problem with the Data Source
1 Check that the Data Source is correct. The Data Source is the name of your server. Open SSMS (SQL Server Management Studio) and double-check the spelling of your server name.

Problem with the SQL user access (User Id and Password)
1 Your connection string must use the username and password created in Configure SQL Authentication logins. Confirm that you followed these instructions to create the SQL user and password to be used in your connection string.
2 Check that the user name and the password are spelled correctly in your connection string. They must match the user created in SSMS.

User login for SQL Server
3 Check that this user’s ‘Server Roles’ and ensure this user has ‘dbcreator’ and ‘public’ roles. The user must have ‘dbcreator’ to allow DoseControl to create the application database.

Microsoft SQL Server Configuration and Connection Issues
👉 Next Steps:
First-time Installation of DoseControl Software
Create a Connection String for DoseControl