No process is on the other end of the pipe (SQL Server 2012)

Question

The server was set to Windows Authentication only by default. There isn't any notification, that the origin of the errors is that, so it's hard to figure it out. The SQL Management studio dont alert, even if you create a user with SQL Authentication only.

So the answer is: Switch from Windows to SQL Authentication:

1. Right click on the server name and select properties;
2. Select security tab;
3. Enable the SQL Server and Windows Authentication mode;
4. Restart the SQL Server service.

You can now connect with your login/password.

Here are the directions by Microsoft: https://docs.microsoft.com/en-us/sql/database-engine/configure-windows/change-server-authentication-mode?view=sql-server-ver15

To solve this, connect to SQL Management Studio using Windows Authentication, then right-click on server node Properties->Security and enable SQL Server and Windows Authentication mode. If you're using 'sa' make sure the account is enabled. To do this open 'sa' under Logins and view Status.

If this didn't work, you may need to reinstall SQL Server

Also you can try to go to services and restart your Sql server instance

So, I had this recently also, for integrated security, It turns out that my issue was actually fairly simple to fix but mainly because I had forgotten to add "Trusted_Connection=True" to my connection string.

I know that may seem fairly obvious but it had me going for 20 minutes or so until I realised that I had copied my connection string format from connectionstrings.com and that portion of the connection string was missing.

Simple and I feel a bit daft, but it was the answer for me.