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.
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'm having an issue with a project I purchased which uses VS 2015.
For some reason I got it to run only once, powered down and never was able to run again. No computer updates were done in between.
I gave all source code and database files to a friend who is very familiar with VS, and he got it to run immediately. He probably also has other VS and SQL version on his computer, so there may be trace elements from those installs making it run - you know how MS stuff works!
This is making me think something different about our computer systems is the issue. I am still waiting to hear back.
I'm getting errors mentioning connection errors or file not found, but the html page describing everything is not clear.
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)
but then error states
A network-related or instance-specific error occurred while
establishing a connection to SQL Server. The server was not found or
was not accessible.
This is not true since I'm able to connect using SQL Server Management Studio.
I've installed everything the seller mentioned to me:
Visual Studio 2015 Community edition
SQL Server Express --- (I installed 2012)
IIS web server
Extensions to install into Visual Studio
Nuget Package Manager
Nunit 2 Test Adapter
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 have written a c# wpf application that talks to a SQL Server 2012 LocalDB on my machine.
To make the app accessible on other peoples machine's I have:
Included the database file in a zip for the user to extract to the programs directory.
Written SQL scripts to attach the database to the local machine's LocalDB instance.
The application works perfectly fine on my machine, however after installing on someone else's computer (after the .NET and SQL Server 2012 LocalDB prerequisites have been installed), it keeps filling up the error logs with the following message:
Exception: 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).
Now there are a lot of other references to the same error message, but I cannot find any that relate to LocalDB or what to try with LocalDB.
Keeping in mind the application is designed for the common 'end-user', so I can't have them following numerous instructions to use SQL Server Management Studio or configuration manager.
The attach SQL script is as follows in case you need to know:
CREATE DATABASE BaseDB
ON (FILENAME = 'C:\MyApp\Base\MyDB.mdf'),
(FILENAME = 'C:\MyApp\Base\MyDB.ldf')
FOR ATTACH;
Can anyone suggest why this wouldn't be working?
To solve this problem:
Install this update to Microsoft Net Framework 4.0: KB2544514
Start: `SqlLocalDB [create|c] instance-name [-s]`
For example:`SqlLocalDB.exe create MSSQLLocalDB -s`