A network-related or instance-specific error occurred while establishing a connection to SQL Server. Server not found or unreachable

Note: This post is from: http://www.jb51.net/article/59352.htm

I'm just afraid that after the article has not, so specially pasted here, so don't blame AH

Here is the content:

A network-related or instance-specific error occurred while establishing a connection to SQL Server. The server was not found or could not be accessed. Verify that the instance name is correct, and that SQL Server is configured to allow remote connections. (provider: Named pipe provider, ERROR:40-Unable to open connection to SQL Server)

Boot discovery this morning, open SQL Server 2008 SQL Server Management Studio, enter the password discovery for SA, unable to log in to the database? The following error is prompted:

"A network-related or instance-specific error occurred while establishing a connection to SQL Server. The server was not found or could not be accessed. Verify that the instance name is correct, and that SQL Server is configured to allow remote connections. (provider: Named pipe provider, ERROR:40-Unable to open connection to SQL Server) "

On the internet to see others said to use the server (local) to replace the cost of localhost, but still no, and then reset the IP itself. Specific as follows:

The following steps require some prerequisites:

Your SQL Server service is already installed, and you cannot find the name of the servers.

1. Open SQL Server Management Configurator

or enter at the command line: sqlservermanager10.msc

2. Click on the MSSQLSERVER protocol and select the TCP/IP protocol on the right page.

3, right click on the TCP/IP protocol, select "Properties", you need to modify the port address of the connection database

4, jump out of the dialog box, there are many TCP/IP ports, find "IP3", change the IP address for their own computer's IP address (or 127.0.0.1) on the TCP port to add 1433, and then select Start

5, "IPALL" all the ports changed to "1433"

6. Restart the service

7, through the above 1-6 steps to set up a good port, reopen SQL Server Management Studio, the server name input: (local) or 127.0.0.1, you can log into the database.

Note: The script of the small part of the recently installed sql2005 is also encountered this problem, is to refer to this method of IP modification to solve. Remember to install the SQL 2005 SP3 patch

VS Error:

A network-related or instance-specific error occurred while establishing a connection to SQL Server. The server was not found or could not be accessed. Verify that the instance name is correct, and that SQL Server is configured to allow remote connections. (Provider:sql network interface, error:26-error locating the specified server/instance)

Workaround: Start the->>sqlserver2005->> Configuration Tool->>sqlserver surface area Configurator->>

Application configurator for service and perimeter connections->> tap remote connection->> Local Area Connection and remote connection->> use both TCP/IP and named pipes->> point "OK"->> Restart SQL Server service but my computer doesn't change, SQL Server Surface Area Configuration Report error message: Change failed. (MICROSOFT.SQLSERVER.SMO) Additional information: Setenable failed for Serverprotocol "TCP". (MICROSOFT.SQLSERVER.SMO) I found a way to solve it. My operating system is also win7: Click the SQL Server 2005 network Configuration "MSSQLSERVER" protocol in SQL Server Config Manager to start the Protocol "TCP/IP" and "Name Pipes". And stop, restart the SQL Server service. Then you can do it.

A network-related or instance-specific error occurred while establishing a connection to SQL Server. Server not found or unreachable