What I want to do is an application that uses a SQL Server 2008 database, but I can't manage to connect to the db.
Here is my code:
public Form1()
{
InitializeComponent();
connection = new SqlConnection("Server=(local);Integrated Security=true");
connection.Open();
CreateDb();
this.FormClosed += new FormClosedEventHandler(Form1_FormClosed);
}
The error that I'm getting says:
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: Named Pipes
Provider, error: 40 - Could not open a
connection to SQL Server)
I am trying to connect using windows authentication...
What am I doing wrong?
Check that TCP/IP connections are enabled in the SQL Server Configuration Manager. Also, if you have installed it as an instance, you will need to specify the server name as .\INSTANCE_NAME.
Try this one :
Data Source=localhost\MyInstanceName;Initial Catalog=myDataBase;Integrated Security=SSPI;
Your instance name is probably SQLEXPRESS or MSSQL (unless you called it something else).
You can find connection string examples on this page:
http://www.connectionstrings.com/
Sounds like either SQL Browser isn't started or isn't configured to respond.
You didn't mention if you're using express or the full blown version... But that probably doesn't matter as the steps are pretty much the same:
http://www.symantec.com/connect/articles/install-and-configure-sql-server-2008-express
Assuming everything is actually installed, start with the "Enable TCP" section.
Serverfault is an excellent source of help on problems like this.
Try suggestions from threads like:
https://serverfault.com/questions/11745/i-cannot-connect-to-my-local-sql-server-2008
https://serverfault.com/questions/94923/a-network-related-or-instance-specific-error-occurred-while-establishing-a-connec
https://serverfault.com/questions/75048/sql-server-connection-issue
https://serverfault.com/questions/111789/how-to-connect-to-local-instance-of-sql-server-2008-express
Most of them suggest checking that the service is running, checking the firewall, checking the user, etc
There are lots of threads matching - search
Although it talks about sql express, this thread looks particularly helpful - https://serverfault.com/questions/191576/sql-server-cant-connect - lots of things to try
Related
I am developing a program with C# and WPF. I want the data to be stored in an SQL Server database. I made a connection string with the instance name in my PC, and that worked. But when I want to connect through the Internet with an IP address, I get some errors:
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. (TCP Provider,
error 0 - No connection could be made because the target machine
actively refused it.)
I enabled TCP/IP, allowed remote connection in SQL Configuration Manager, opened a port of 1433 in my firewall, but still I am getting this error.
My connection string is this:
String connString = #"Network Library=dbmssocn;
Network Address=127.0.0.1,1433;
Integrated security=SSPI;
Initial Catalog=db";
SqlConnection conn = new SqlConnection(connString);
conn.Open( );
Where is my mistake?
There is very slight error in your connection string and honestly I can't blame you for that as it is very weird way in which SQL Sever is behaving. I'm not sure if this error lies in connection provider side or SQL Server instance side. Name of Network Library that your application is using to connect to the SQL Server using dbmssocn(Win32 Winsock TCP/IP) should always be mentioned in capital letters. Though I didn't see any relevant MSDN documentation from MS to support my statement but it actually worked when I did so. Here is the connection string that you should be using to fix the error.
String connString = #"Network Library=DBMSSOCN;
Network Address=127.0.0.1,1433;
Integrated security=SSPI;
Initial Catalog=db";
Seriously, I got freaked out in reproducing your issue as instead of copying the connection string from your question I copied it from some other blog :). But all is well that ends well. I've also assumed that a database named "db" actually exists on the default (NOT named instance) instance of the sql server you are connecting to when typing this answer. If changing the casing of network library name in connection string doesn't help then double check that database "db" must exist for a sql server default instance to which you are connecting to. In case you are using a named instance of sql server in your installation then that instance name should also come in the connection string.
Configure your SQL Server to allow TCP/IP connections. Go to SQL Server Configuration Manager -> network then protocols for your SQL Server named instance -> TCP/IP.
See this image!
I recently upgraded to Windows Server 2012 from 2003. It was a big IIS jump from 6 to 8.5. I cannot seem to get a named SQL Server instance on an alternate port to work in my ASP.net 4.0 website.
The connection string I am using is:
<add name="MyConn"
connectionString="Server=192.168.12.5\stage,7839;Database=mydb;uid=myun;pwd=mypw;" />
When the website tries to load in the browser, I get the following error:
[HttpException (0x80004005): 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: TCP Provider, error: 0 - No connection could be made because the target machine actively refused it.)]
We've checked firewall settings to no avail. Is the syntax correct in the above example? I've done numerous searches and found examples of people using
192.168.12.5:7839\stage
or
192.168.12.5\stage;port=7839;
but both of those give syntax errors.
I need some confirmation on the correct syntax for the web.config file. Any help is greatly appreciated, thanks!
Can you go to SQL Server > Configuration Tools > Configuration Manager and see if that instance is really named what you think it is?
You should see something like this:
The entries SQL Server (instacename) on the right hand side show you what instances you have - they should be in state running, and the instance name is in the brackets. If it's MSSQLSERVER, then it's an unnamed default instance - otherwise it's the instance name. Is your instance name correct, as expected - and running?
I am trying to create a new SQL DB in Visual Studio 2010, and Upon entering a Server Name and a DB name then pressing Ok, I get this 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: Named Pipes Provider, error: 40 - Could not open a connection to SQL Server)
Any ideas?
Just go through this article.I think you can solve the problem.
http://blog.sqlauthority.com/2009/05/21/sql-server-fix-error-provider-named-pipes-provider-error-40-could-not-open-a-connection-to-sql-server-microsoft-sql-server-error/
Also ensure you have specified servername and database name correctly in connection string.just take connection string from property window of added database.
Try this article, it goes through pretty much all the steps you will need to troubleshoot your connectivity problems:
http://social.technet.microsoft.com/wiki/contents/articles/2102.how-to-troubleshoot-connecting-to-the-sql-server-database-engine.aspx
I write web page in MVC, which use Entity Framework as ORM mapper. I put my connection string to web.config file. Here is it:
<add name="JP_CMS" connectionString="Data Source=.;Initial Catalog=JP_CMS;
User Id=CmsWebUser;Password=abcd1234abcd1234;"
providerName="System.Data.SqlClient"/>
I try to get data by this C# code
public DataBaseContext()
: base("JP_CMS")
{
Database.SetInitializer(new DropCreateDatabaseIfModelChanges<DataBaseContext>());
}
//------------------------------
var db = new DataBaseContext();
var result = db.Articles.ToList(); //<- here is thrown exception
//------------------------------
My local SQL server is running, this table is exists, but I get excepion like in this:
I think it is the most important expection: "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: Named Pipes Provider, error: 40 - Could not open a connection to SQL Server)"
Could you help my by give some idea what I make wrong?
"The system cannot find the file specified" error. Check carefully your connection string.
hi Error indicates EF tried to connect to the server but failed.
Could you Checkk,
1) SQL Server should be up and running.
Go to All Programs >> Microsoft SQL Server 2008 >> Configuration Tools >> SQL Server Configuration Manager >> SQL Server Services, and check if SQL Server service status is “Running”.
In addition, ensure that your remote server is in the same network. Run “sqlcmd -L” in your command prompt to ascertain if your server is included in your network list.
2) Enable TCP/IP in SQL Server Configuration
For more info you can go here
Instead of DataSource =. try DataSource = .\sqlInstanceName. Also DataSource=(local) might work.
I took an old software made by someone else, which need to connect to a database with the .mdf extension.
But when I run the software, I have an error 26. I have obviously checked Google and it seems the the main problem is the firewall. But if I disable it the problem doesn't dissapear.
Here is the code for connect the database :
DataClasses1DataContext db = new DataClasses1DataContext(Environment.CurrentDirectory + "\\bddgestionvin.mdf");
I've noticed, when I try to connect the database with the datacontext class it fail too with the same error 26. (see attached screenshot below)
The string connection used by this class is :
Data Source=.\SQLEXPRESS;AttachDbFilename=|DataDirectory|\bddgestionvin.mdf;Integrated Security=True;Connect `Timeout=30;User Instance=True`
I know I'm a little vague but I never did that kind of stuff (connect to a .mdf database) And the code is not mine, feel free the ask further explanation / code. Any help is welcome !
P.S The error message is
SqlException was unhandled 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)
(Sorry for the french software)
Hi I don't know you may see these steps. Make sure that these steps should pass.
The reason that we get this error message is the client stack could
not receive SSRP response UDP packet from SQL Browser. It's easy to
isolate the issue. Here are the steps:
1) Make sure your server name is correct, e.g., no typo on the name.
2) Make sure your instance name is correct and there is actually such
an instance on your target machine. [Update: Some application converts
\ to . If you are not sure about your application, please try both
Server\Instance and Server\Instance in your connection string]
3) Make sure the server machine is reachable, e.g, DNS can be resolve
correctly, you are able to ping the server (not always true).
4) Make sure SQL Browser service is running on the server.
5) If firewall is enabled on the server, you need to put
sqlbrowser.exe and/or UDP port 1434 into exception.
You can read more from here
You can also try PortQry and validate your firewall does not block SQL Browser UDP packet
A network-related or instance-specific error occurred while establishing a connection to SQL Server. Failed to establish a connection with SQL Server.
The server was not found or was not accessible.
May be server is stopped, you don't have permission to access the server, or the instance name is not correct .
Verify that the instance name is correct and that SQL Server is configured to allow remote connections.
Please goto SSMS and try connecting the server. Verify the SQL Server is running and your account is configured to access the service.
(provider: SQL Network Interfaces, error: 26 - Error Locating Server/Instance Specified)
Thanks