Hello,

I'm sorry if this has already been answered somewhere else, I didn't find anything that helped.

Setup:
Two VMs running Windows Server 2012 R2 Datacenter, one running SQL Express.
When trying to connect to the SQL Express, the connection does not work.

Here's what I've done so far:
Set up the MSSQL instance, named SQLEXPRESS
Set up a database, named TESTDB
Set the instance to mixed authentification
Set up VM endpoint TCP 1433
Opened ports TCP 1433, 1434 in the firewall
Activated the SQL Browser
Activated the TCP/IP-Service in the SQL Server Network Configuration

Testing connection via UDL file with the following information:
Server name: <cloud storage>.cloudapp.net\<sql server>\SQLEXPRESS
Username: sa
Password: <password>
Database: TESTDB

Now it returns the following error:

"Test connection failed because of an error in initializing provider.
[DBNETLIB][ConnectionOpen (Connect()).]SQL Server does not exist or access denied."

Now I keep reading that it may be a firewall problem. But I turned off the firewalls on both servers completely for testing purposes (they're test servers and will be deleted anyway) and it still doesn't work.

I know I must have forgotten something, but what? Or am I entering the wrong connection information?
Does anyone know?

Regards
~Irolan

• Edited by Irolan Thursday, January 29, 2015 4:33 PM
• Moved by Guy Haycock [MSFT]Microsoft employee Friday, January 30, 2015 1:08 AM

Did you restart the SQL server instance service after setting the instance to mixed authentification?

Server name: <cloud storage>.cloudapp.net\<sql server>\SQLEXPRESS

Hello,

I wonder about the Server Name, it should be "MachineName\SQLEXPRESS" only.