My VB.Net code connects to SQL Server. On my PC, it succeeds. On IIS running on the same machine as SQL Server, it fails. Any ideas?
I've tested:
I've tried IP address and server name. Same result.
I've tried Integrated Security and I've tried username/password. Same result.
On the server machine, Excel and SSMS can connect to SQL server using the same server name, username and password.
The fact that my PC can connect excludes many common problems including: ip address, server name, port, firewall, turn on sql server, connection string, credentials, permissions, sql roles.
Server (IIS and SQL) info: VB.Net, connection string providerName="System.Data.SqlClient", Windows Server 2008 SP2.
My PC info: Run website in Visual Studio 2019. Connects to same DB using same connection string (not local db and not as a different user).
Code (fails on second line):
oConn = ConnectionService.DatabaseName.Connect
oConn.Open()
Connection string: connectionString="Data Source=IP Address\SQLEXPRESS;Initial Catalog=DatabaseName;Integrated Security=False;Persist Security Info=False;User ID=Username;Password=Password;" providerName="System.Data.SqlClient"
Error message: System.Data.SqlClient.SqlException (0x80131904): 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) ---> System.ComponentModel.Win32Exception (0x80004005): The network path was not found
Oops. Right after posting this, I found out Web.Config pointed to a different connection string. That should explain and solve everything. I had checked Web.Config, but it turns out that that wasn't the one this server was using.
Related
I'm creating a simple UWP application working together with my local DB server I set up with SQL Server Management Studio.
I can successfully set up a connection in the server explorer and run queries in the DB:
However when I run the application I get an error when the connection is being established:
System.Data.SqlClient.SqlException HResult=0x80131904 Message=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: 25 - Connection string is not valid) Source=Core .Net SqlClient Data Provider
I'm not sure if it's a problem with the connection string or what else it could be. I checked the firewall settings and everything seems to be fine. The SQL server settings also allow for remote connection.
Which SQL Server version is running?
Have you tried with the following connection string format?
Data Source=.\\MSSQLServer;Initial Catalog=PapaDario;Trusted_Connection=yes;
Before you connect to your database, some aspect of the SQL Server configuration needs to be changed. First, ensure that you've enabled TCP/IP for SQL Server. You can do that in the Computer Management console. Then make sure that your SQL Server Browser service is running.
I'm currently developing a program using Visual Studio 2010 and SQL Server 2008 R2.
I'm currently facing a problem while connecting to a SQL Server. For starters, I have a station with IP 192.168.15.101 establishing a connection to a SQL Server with IP 192.168.0.11.
This station can successfully ping the server, and I can also connect to SQL Server located in the server from SQL Server Management Studio. The code below runs smoothly as well :
.extQuery = *SQL Query Here*
Try
If InternalSupport.RefreshConnection(False, GlobalVar.connectionString, GlobalVar.Server, False) Then
.command = New SqlCommand(.extQuery, .connect)
.reader = .command.ExecuteReader
While .reader.Read
*Some Code Here*
End While
.reader.Close()
.command.Dispose()
.connect.Close()
Catch ex As Exception
*Error Handling Here*
End Try
However, the problem lies when I tried to refill my Table Adapter for VS Built in Data Source. Whenever I call the code below :
Me.TEMPORARY_DUETableAdapter.Fill(Me.DsAscendPending.TEMPORARY_DUE)
It raises 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)
What I have tried are :
Allow Remote Connection on SQL Server on Server side.
Set Connection String Dynamically from code.
Disabling windows firewall and antivirus.
Make sure all the ports and IP in SQL Server are open
Connect SQL Server from SQL Server Management Studio located on remote location, and it connects perfectly.
Any help on this error is greatly appreciated. Thanks!
SOLUTION
I've found the solution. The problem lies in my Connection String. I was using server computer name as Data Source instead of IP.
Below is my previous Connection String :
connectionString="Data Source=MAIL-SERVER;Initial Catalog=MG_CreativeLab;Persist Security Info=False;User ID=sa;Password=#adminmedan123#"
It will allow connection from the same IP Segment, while rejecting connection from other segments
Here's the correct connection string :
connectionString="Data Source=192.168.0.11;Initial Catalog=MG_CreativeLab;Persist Security Info=False;User ID=sa;Password=#adminmedan123#"
Thank you for the response!
I've found the solution. The problem lies in my Connection String. I was using server computer name as Data Source instead of IP.
Below is my previous Connection String :
connectionString="Data Source=MAIL-SERVER;Initial Catalog=MG_CreativeLab;Persist Security Info=False;User ID=sa;Password=#adminmedan123#"
It will allow connection from the same IP Segment, while rejecting connection from other segments
Here's the correct connection string :
connectionString="Data Source=192.168.0.11;Initial Catalog=MG_CreativeLab;Persist Security Info=False;User ID=sa;Password=#adminmedan123#"
Thank you for the response!
I'm working on one Windows forms application using one .mdf file. And I have Sql Server 2008 installed in my machine , it is working fine in my machine. Now I need to install this application in Client's machine, Client's machine don't have Sql Server if they try to access this getting Network related exception, ie,
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)
and this is my connection string in app.config file,
<add name="CustomConnection" connectionString="Integrated Security=True;MultipleActiveResultSets=True;Connect Timeout=120;User Instance=True;AttachDbFilename=C:\Users\[username]\AppData\Roaming\Smart\App_Data\SampleDB.mdf" providerName="System.Data.SqlClient" />
Can we access the .mdf file without Sql Server instance? If yes how can we set the ConnectionString value.
Thanks,
Abhishek
I recently added a second site to my server. That site gives me the dreaded:
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)
I have no idea why I am getting this. I've gone through this and this to no avail. This is a new MVC4 application I have at beta.vinformative.com in IIS 7. The other site is a MVC3 site at vinformative.com. It is running fine. Both of their databases have the exact same connection string and they are both on the same SQL server. I've given the same user mapping and role membership for NT Authority\Network Service to both databases.
Here is what I've tried so far:
MSSQLSERVER SQL Server service is running along with SQL Server Browser, and SQL Server Agent
I've added a firewall inbound rule for SQL Server browser
Made sure TCP/IP is enabled in sql server configuration
Added port 1433 TCP to the firewall
Enabled remote connection to db server
Successfully pinged the machine
Used portqry to see the db server on UDP 1434
I can connect to the site locally when I am remotely logged into my server. Furthermore, I have an ELMAH instance in the application for error logging and that is updating the database correctly. I feel like I am taking crazy pills because this should be working and I can't find an outright error. Please help!
Here is my connection string
<add name="vfContext" connectionString="Data Source=vinformative;Initial Catalog=vf3;Integrated Security=True" providerName="System.Data.SqlClient" />
Could be EF - see here.
Also, remote access cannot work with "Integrated Security=True" as far as I know, should use "User ID=******;Password=****;Integrated Security=False".
When I use the local IIS Web server, my ASP.NET MVC application is unable to connect to SQL Server. The database is on another server. However, if I use the Visual Studio Development Server, it works just fine.
Anyone know what settings I'm missing? Should something change in my Web.config?
Yes, TCP/IP is enabled on SQL Server.
Here is the error I get -
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)
Here is my connection string -
connectionString="
SERVER=servername;
Initial Catalog=dbname;
User ID=userid;
Password=passwd"
providerName="System.Data.SqlClient"
I think you need to use IP address to connect remote database something like SERVER=59.230.212.12 in connection string. Try to connect database in management studio from where your IIS is installed . then use same setting in connection string .