I have a strange problem. I have a test server where I run my applications for people to test internally. It has a local instance of SQL Server Express, IIS with .NET 4.6 installed. To be clear firewall is completely turned off.
I've inherited some code that I can't run on the server. The application starts up fine but when I try to write or read from the DB I get the following:
A connection attempt failed because the connection party did not properly respond after a period of time, or established connection failed because connected host failed to respond
What makes this issue weird is that I can locally connect to the database on the server. I can run the application on my local machine connecting to the database on the server. When I change the connection strings to something incorrect it throws this error.
So from what I can tell, the database is running fine. The application compiles fine on local machine and still connects to the database on the server. It's just when the application is hosted in IIS it's timing out connecting to the database.
The application is an ASP.NET MVC app.
If you can point me to any kind of reading or anything.
I'm currently working on an API, to access data from a SQL Server that is hosted locally. My app is being hosted through an Azure web app. I'm also using Entity Framework 6 in my application to access data. Since my data can't be in the cloud, I created an Azure Hybrid connection to create a relay to my SQL Server.
However, I keep running into this error (see below). I don't understand why this happens. I have checked my firewall rules to make sure that connections from Azure are being permitted. I have also verified that my connection string is correct and that I'm using the right port number. I also verified that remote connections are allowed on the SQL Server.
In case anybody is wondering I'm running SQL Server 2012. Does anyone have a fix for this issue? I would really appreciate it.
Thanks in advance.
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.
I'm very frustrated. I have a website running on Visual Web Developer 2008 Express with my local database, everything works great. I also have the same web site running on a production server. Everything was working great but tonight I did a "reset" on production.
I deleted a couple of table, re-created them and inserted data. Everything was ok at this time.
I deleted ALL the files via the FTP.
I used the module called "Copy website" in visual studio and copy the site to the website via FTP.
When I log on my website, here is the error I got:
Server Error in '/' Application.
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)
Description: An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code.
Exception Details: System.Data.SqlClient.SqlException: 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)
Nothing has changed related to SQL connection, this is OLD code that I always used.
My website is completely paralysed because of this and I feel sick inside because I feel there is nothing I can do.
Can anyone help me please?
Your connection string was probably overriden when you copied your new website version on the server. Please check the connection string in web.config and see if it is valid.
If you are connecting from Windows Machine A to Windows Machine B (server with SQL Server installed) and are getting this error, you need to do the following:
On Machine B:
Turn on the Windows service called "SQL Server Browser" and start the service
In Windows Firewall:
enable incoming port UDP 1434 (in case SQL Server Management Studio on machine A is connecting or a program on machine A is connecting)
enable incoming port TCP 1433 (in case there is a telnet connection)
In SQL Server Configuration Manager:
enable TCP/IP protocol for port 1433
I've resolved the issue. It was due to the SQL browser service.
Solution to such problem is one among below -
Check the spelling of the SQL Server instance name that is specified in the connection string.
Use the SQL Server Surface Area Configuration tool to enable SQL Server to accept remote connections over the TCP or named pipes protocols. For more information about the SQL Server Surface Area Configuration Tool, see Surface Area Configuration for Services and Connections.
Make sure that you have configured the firewall on the server instance of SQL Server to open ports for SQL Server and the SQL Server Browser port (UDP 1434).
Make sure that the SQL Server Browser service is started on the server.
link - http://www.microsoft.com/products/ee/transform.aspx?ProdName=Microsoft+SQL+Server&EvtSrc=MSSQLServer&EvtID=-1
check forthe followings :
Make sure your database engine is configured to accept remote connections
• Start > All Programs > SQL Server 2005 > Configuration Tools > SQL Server Surface Area Configuration
• Click on Surface Area Configuration for Services and Connections
• Select the instance that is having a problem > Database Engine > Remote Connections
• Enable local and remote connections
• Restart instance
Check the SQL Server service account
• If you are not using a domain account as a service account (for example if you are using NETWORK SERVICE), you may want to switch this first before proceeding
If you are using a named SQL Server instance, make sure you are using that instance name in your connection strings in your ASweb P.NET application
• Usually the format needed to specify the database server is machinename\instancename
• Check your connection string as well
the cause is that SQL SERVER is stopped from services.msc
a solution for this problem could be starting SQL SERVER from services.msc
I recently had this problem and it ended up being a port issue. My production SQL Server was set up at to be port 1427 instead 1433.
Just change the connection string to be
...data source=MySQLServerName,1427;initial catalog=MyDBName...
Hope this helps anyone who might be seeing this same issue.
I had the same problem with SQL Server 2008 R2 and when I checked "SQL Server Configuration Manager" My SQL Server instance had Stopped. Right Clicking and Starting the Instance solved the issue.
we have to enable TCP/IP property in sql server configuration manager
If your server was working and suddenly started erroring out, your server/instance stopped and connection settings were changed somehow.
For SQL Server 2008 here is how you can fit this:
Goto Start > All Programs > SQL Server 2008 > Configuration Tools > SQL Server Configuration Manager > SQL Server Services.
And here you'll see all the instances and their state.
The state of the instance you were trying to connect can be stopped here.
Double click on the instance and then click on connect.
It will connect and now go back and run your application, you will be able to connect with no error.
This solution assumes the error is not being caused by something wrong in your connection string.
In my case it was a very silly error. I was using a library to read the connection string out of a config file, and I forgot to double back slash.
For example I had:
localhost\sqlexpress which was read as localhostsqlexpress
when I should rather have had
localhost\\sqlexpress note the \
I had same problem regarding that i.e A network-related or instance-specific error occurred while establishing a connection to SQL Server.
I was using SQL Server 2005 (.\sqlexpress)` and worked fine but suddenly services stopped and gave me error.
I solved it like this,
Start -> Search Box - > Sql Configuration Manager -> SQL Server 2005 Services >and just Change Your SQL Server (SQLEXPRESS) State to Running by right clicking that service Sate.
I solved this issue by running the following command in an elevated command prompt as specified in this post.
net start mssqlserver
I had the same problem but found that it was because the password for my Service Account for the Database Engine had expired. The solution was to login to that account, fix this, then set the account so password never expires.
My remote sql server was expecting connection at a different port and not on the default 1443.
The solution was to add a "," after your sql server IP and then add your port like so 129.0.0.1,2995 (Check the " , " after server IP)
Please find the image for reference below.
I had the same error, and it turned out .NET created a database on localhost which I wasn't aware of. When I tried to get the site live it didn't create the database, so the code was pointing to a database that was non existent.
Hopefully this might help some other people out trying to troubleshoot.
My application is throwing error from a client machine of not able to connect to the database. So as a test I use SQL Management Studio 2008 on that same client machine to try and connect to the database and I found out that if I use IP\InstanceName then I can connect but if I use ServerComputerName\InstanceName then I can't connect. I have verified the following:
The server has the same gateway and subnet mask as the client.
I can ping the server using either its IP address or its computer name.
No Firewall on either server or client machine.
Verify Server SQL browser service is running.
Verify Server is set to allow remote connection.
Verify Server TCP/IP is enabled via SQL SErver Configration Manager.
I can connect from a different client machine using ServerComputerName\InstanceName
Both server and client are using static IP setup with no DNS server under IPV4 properties.
Tracert from client to server shows only one hop, that is directly to the server machine IP.
I can remote access the client machine from the server machine or viceversa using host name.
I then go to the server machine and connect using LNKLAB8\Xmark (LNKLAB8 is the host name and Xmark is my instance name) and I connected successfully. However, when I run the command SELECT ##SERVERNAME, the result I got back is LNKLABARIAL8\XMARK
This baffled me, because if I right click on the database properties as per the screenshot below, it shows LNKLAB8/Xmark .. am I going crazy or something weird going on here? after taking at the steps I've taken, do you have any suggestion of how I can get the client machine to connect to the database using the server host name instead of the server IP address?
I've kind of hit the wall on this issue, I'm unsure if I am facing a network related issue or it is a database setting issue.
Edit: When I tried to connect using host name to the server DB I would get the following:
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)
Try add servers IP and Name to c:\WINDOWS\system32\drivers\etc\hosts
1) Make sure you've enabled TCP/IP (Configuration manager), and restarted MSSQL
<= it sounds like you've done this.
2) Make sure you can "ping" by hostname and by IP
<= It sounds like you've done this, too
3) Make sure MSSQL Browser is running
4) If you're using Windows authentication (vs. SQL Mixed), then make sure you can authenticate to the remote server:
net use \\remote-server /user:<name> <password>
5) Failing all else, you might want to consider reinstalling MSSQL-related components on either/both client or server (for example, MDAC)
Links:
http://social.msdn.microsoft.com/Forums/sqlserver/en-US/4d2ce34a-508f-4a1d-8828-8806ccc12f77/sql-server-2005-cant-connect-remotely-using-host-name?forum=sqlsetupandupgrade
http://blogs.msdn.com/b/sql_protocols/archive/2007/05/13/sql-network-interfaces-error-26-error-locating-server-instance-specified.aspx
https://serverfault.com/questions/384700/error-connection-to-sql-server-using-hostname-instance-or-fqdn-instance-ip
'Hope that helps!
I noticed this:
8: Both server and client are using static IP setup with no DNS server under IPV4 properties.
How is name resolution happening, then? WINS? NetBIOS? Sql Server may not like that. Try checking that you have a working DNS server with the appropriate entry for your Sql Server system, and things may work better.
i made an app on c# which has database connection and application works fine on my developement pc!
Application starts fine and everything else works fine which has nothing to do with DB but it throw an error when i try to execute query ?
I have Dotnetfx 2.0 installed on target machine what do i need to? Sql server?
Error is:
An error has occured while establishing a connection to the server. When connecting to SQL server 2005, this failure may be caused by the fact that under the default settings SQL Server does not allow remote connections. (provider: SQL Network Interfaces, error: 26 - Error Locating Server/Instance Specified
p.s. its my first db application =S
SQL Server is a completely separate application from the application you wrote and are distributing. If your application does not connect to an existing SQL Server running somewhere on the network you will have to install and configure SQL Server as part of your application's installation.
In addition you will either need to install / create a database as part of your application's installation, or else your application needs to be able to detect the absence of the database and build it itself on first startup.
As Marek said, the connection string is the most likely culprit, and I believe on SQL 2008 you have to explicitly allow TCP connections via:
SQL Server Configuration manager
Select SQL Server Network
Configuration Select Protocols for your instance
Right click on TCP/IP and "Enable"
Make sure your connection string looks something like this:
"Server=(local)\\SQLEXPRESS;Database=Your_DB_Name_Here;uid=sa;pwd=password;"