无法将实体框架连接到本地SQL Server Express

Question

I have the connection string:

  <connectionStrings>
    <add name="SolrLocal" providerName="System.Data.SqlClient" connectionString="Data Source=.\SQLExpress;Initial Catalog=SpeedOfLightRailDB;Integrated Security=true" />
  </connectionStrings>

But I'm getting the error:

"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)"

This is my first time playing with SQL Server Express so I might be missing something obvious....

Can anyone at least confirm that this is what the connection string should look like for Entity Framework -> SQL Sever Express? I've been changing it around trying to get it to work.

Answer 1

1. Check your windows services and make sure that the sql server express windows service is running. You can get to services by running services.msc from the RUN command bar (windows key + R). If it is not running then start it.
2. Do you have Sql Server Management Tools installed? If so you can try to connect using those tools. If you cant connect to your sql server express instance from there, most likely you will not be able to connect from code either. If you do not have this installed no worries, you can still test it with the next step.
3. If you need help building the connection string this next one is a great way to do it. Create a text file on your desktop. Rename the extension from .txt to .udl . Open the file and you will get a Data Link Properties screen, start with the 1st tab (it defaults to tab 2) and then fill in the second one also. Once you test your connection here and it works you can open the file using NotePad or rename the extension back to .txt and open it in NotePad . The connection string will be on the 2nd line in the text file. Just copy and paste it to your .config file.

If none of this works then report back with what you have found and any errors you are getting.

Answer 2

Try this:

<connectionStrings>
    <add name="SolrLocal"
        providerName="System.Data.SqlClient"
        connectionString="Data Source=.\SQLEXPRESS;Initial Catalog=SpeedOfLightRailDB;Integrated Security=True;MultipleActiveResultSets=True"/>
</connectionStrings>

Also check if .\\SQLEXPRESS is accessible from SQL Server Management Studio, and if SQL Server is configured to allow remote connections in SQL Server Configuration Manager.

It can be launched from cmd like this: C:\\Windows\\SysWOW64\\mmc.exe /32 C:\\Windows\\SysWOW64\\SQLServerManager12.msc

Answer 3

You are using .\\SQLExpress and I think your local servername is different. What you can do is open your SQL Server and then while connecting see the server name used. You must enter the same name in your web config. Refer the below image which shows the server name while connecting to the SQL server, In my case I need to replace .\\SQLExpress with RAJSHEKAR-PC\\SQLEXPRESS