Question

I am trying to connect to the database but I am getting this exception:

A network-related or instance-specific error occurred while establishing a connection to
SQL Server. The server was not found or was not accessible. Verify that the instance name 
is correct and that SQL Server is configured to allow remote connections. 
(provider: SQL Network Interfaces, error: 26 - Error Locating Server/Instance Specified)

I’ve googled a lot, but I could not find the answer.

Here’s my configuration:

I use MS SQL Server 2008 Express. Both Sql Server and Sql Server Browser use my account (I am an administrator). I’ve also used local system and local service. Without success.

Here is my connectionstring in app.config:

<?xml version="1.0"?>
<configuration>
  <connectionStrings>
    <add name="EventManagerEntities" connectionString="metadata=res://*/Entities.RelationModel.csdl|res://*/Entities.RelationModel.ssdl|res://*/Entities.RelationModel.msl;provider=System.Data.SqlClient;provider connection string=&quot;Data Source=martijn-laptop\sql2008;Initial Catalog=EventManager;Integrated Security=True;MultipleActiveResultSets=True&quot;" providerName="System.Data.EntityClient"/>
  </connectionStrings>
<startup><supportedRuntime version="v4.0" sku=".NETFramework,Version=v4.0"/></startup></configuration>

I’ve also tried to use the sql server username and password, also without success.

I am using winforms. What else can I try?

When I check netstat -an I get this:

TCP    0.0.0.0:1433           0.0.0.0:0              LISTENING
TCP    [::]:1433              [::]:0                 LISTENING

I don’t think this is correct, right? But how do I set it right?

Answer 1

It cannot find instance/server. Telnet the 1433th or the configured port of martijn-laptop\sql2008 to verify its accessible