I setup a new user in SQL Server Express 2017, I've enabled Windows and SQL Server authentication, as well as tcp/ip for SQL Server. Using the following settings, I'm able to login with SQL Server Management Studio:

 

Server type: Database Engine

Server name: xxxxxx\SQLEXPRESS

Authentication: SQL Server Authentication

Login: myuser

Password: mypassword

 

Login, browsing the database, and updating records works without a problem.  However, browsing to the DNN site, I receive "DNN Error Connection To The Database Failed." Using the same details as above in my connection strings:

<connectionStrings>

   <add name="SiteSqlServer" connectionString="server= xxxxxx\SQLEXPRESS;database=mydb;uid= myuser;pwd= mypassword;" providerName="System.Data.SqlClient" />

</connectionStrings>

<appSettings>

    <add key="SiteSqlServer" value="server=server= xxxxxx\SQLEXPRESS;database=mydb;uid= myuser;pwd= mypassword;" />

 

I am using SQL Server Authentication, not Windows Authentication. 

Jason,

is the SQL Server on the same machine as the web server, or is it a different machine?

If these are different machines: are the two machines in the same domain? Can you connect to the database using a UDL file on the web server (or from a SSMS installed on the web server)? If no: Have you checked the Firewall settings?

Happy DNNing!
Michael

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