I'm new to network computing. I am trying to build an ASP .NET database connection string. I have an Application windows 2012 server VM and an SQL windows 2012 server VM. My AD user is Administrator with a password. I have windows authentication turned on. Here is my connection string and VM information:
Domain: SQL.com
DB VM server computer name: win-5c3qtg1rebc.sql.com
From the Application server VM I can ping this computer name for the SQL VM: win-5c3qtg1rebc
ASP .NET connection string: #"Data Source=win-5c3qtg1rebc;Initial Catalog=KML;Integrated Security=SSPI"
When I run my application from Visual Studio I get the error:
"System.Data.SqlClientSqlException: 'A network-related or instance-specific error occurred while establishing a connection to SQL server. The server was not found or was not accessible."
Can someone look at my connection string and see what the problem is?
Thanks in advance.
Related
I'm currently doing a project for a client. And for the database I'm using localDB and for deployment I'm using ClickOnce. My database name is Database.mdf and the connection string is
Data Source=(LocalDB)\MSSQLLocalDB;AttachDbFilename=|DataDirectory|\Database.mdf;Integrated Security=True
When I launch this application, it works fine on my computer. However when I install it on another computer I get 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: 50 - Local Database Runtime error occurred. The specified LocalDB instance does not exist.)
I have looked for answers in other forums as well however nothing seems to work. Can anyone tell me what the problem is?
Edit: I have included LocalDB and .Net Framework 4.6.1 as prerequisite.
Edit 2: The above problem was fixed but I have a new error now! It says that it cannot create the database because it is version 852 and this server supports version 706 and earlier!
Error Image
Check whether you able to connect with this localDB string in the SQL Management Studio. If you unable to connect with this. then this connection string is not valid
check your connection string here: Unable to connect to localDB in VS2012 – "A network-related or instance-specific error occurred while establishing a connection to SQL Server..."
I published my ASP.NET Core application to a Windows Server 2012 environment. I made a new website, pointed it to the folder and it was running fine. Now I am trying to make the application connect to a database. I installed SQL Server Express 2016 and edit my project so it retrieves data from the database. put my 'KSP_Backend.mdf' file to my server and I attached the file in SQL Server Management Studio. The database is completely visible, so it exists.
Now, when I try to run my project in my published project folder 'dotnet KSP_Backend.dll', it gives me the following error:
Unhandled Exception: System.Data.SqlClient.SqlException:
A network-related or instance-specific error occurred while establishing 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: 50 - Local Database Runtime error occurred. Thespecified LocalDB instance does not exist.)
This is the connection string in the 'appsettings.json' file I used:
"Server=<My server's name>\\KSPSERVER;Database=KSP_Backend;Trusted_Connection=True;MultipleActiveResultSets=true"
I'm just not sure anymore if the connection string caused my error. My firewall is off and LocalDB is up and running.
I had the same issue when I didn't have 'Remote connection' enabled on the DataBase's Server.
In SQL Management Studio, right click the Server name, then Properties, go to tab Connections, make sure that Allow remote connections is enabled.
Another thing could be that the SQL Server TCP/IP protocol is not enabled.
In SQL Server Configuration Manager, click on SQL Server Network Configuration in the left pane and right-click TCP/IP and select Enable.
Finally, you might need to configure SQL Server Express to listen to a static port. You can find a good reference for this and the previous points here: SQL Express Remote Connections.
This is the first time I've ever had to use a Windows server for publishing so forgive my ignorance.
I have a dedicated server with Windows Server 2012 r2 installed. I have setup the FTP publishing in order to publish the site via Visual Studio. The site works fine unless I try and use a feature that requires a database connection.
The project I am developing uses EntityFramework to handle the SQL database.
And I receive the following error:
Exception Details: System.ComponentModel.Win32Exception: The system
cannot find the file specified
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: 52 - Unable to locate a Local Database
Runtime installation. Verify that SQL Server Express is properly
installed and that the Local Database Runtime feature is enabled.)]
Connection strings
CentralDb
metadata=res://*/CentralDb.csdl|res://*/CentralDb.ssdl|res://*/CentralDb.msl;provider=System.Data.SqlClient;provider connection string="data source=(LocalDB)\MSSQLLocalDB;attachdbfilename=|DataDirectory|\centraldb.mdf;integrated
DefaultConnection
Data Source=(LocalDb)\MSSQLLocalDB;AttachDbFilename=|DataDirectory|\aspnet-BetCentral-20161230033657.mdf;Initial Catalog=aspnet-BetCentral-20161230033657;Integrated Security=True
LocalSqlServer
data source=.\SQLEXPRESS;Integrated Security=SSPI;AttachDBFilename=|DataDirectory|aspnetdb.mdf;User Instance=true
I've done a bit of Googling for this error and I have found multiple answers that are very varied and have not helped me correct my problem.
I am currently developing an ASP.NET app using Visual Studio Code on mac.
I am trying to use "mssql extension" to get connection with a SQL Server database.
I followed https://learn.microsoft.com/en-us/sql/linux/sql-server-linux-develop-use-vscode step by step. However, I always get an error message like below:
mssql: Failed to connect: 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: TCP Provider, error: 40 - Could not open a connection to SQL Server)
"error message screenshot"
Thanks for your help in advance.
If this is a SQL Server 2008 R2 instance, you need to upgrade to SP3. See https://github.com/Microsoft/vscode-mssql/issues/666 for details - basically .Net Core doesn't support older versions due to a vulnerability that is fixed in SP3, and the MSSQL extension uses the .Net Core stack for connectivity.
I have created a desktop application with visual studio 2012 and Sql Server 2008 R2 and want to deploy the application on client machine.I am using clickonce technique to deploy the application.How should I deploy the database on client machine or what connection string should be mentioned during publishing the application.By default the connection string is :
Data Source=.;AttachDbFilename=|DataDirectory|\DatabaseName.mdf;Integrated Security=True
When I create a clickonce application 3 files get created
setup.exe
ABC.Application
Folder named Application files
When I click on setup.exe necessary setup get installed but when i try to access the database from installed application it throws error :
*Unhandled exception has occured in your 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: Named Pipes Provider, error: 40 -
Could not open a connection to SQL Server) *