Sql ошибка 26 при обнаружении указанного сервера или экземпляра - ErrorsMaster.ru

This issue also confused me a few days, after the IT guy changed some security settings on the SQL Server.

I have an EntityFramework for the Web application and for a desktop application.

After I changed some settings on the SQL Server, the Web application comeback to work, but the desktop still facing issue. But I used the same connection string for both applications, it make no sense one is working but the other doesn’t.

Then I searched a lot until I found someone saying here it is needed to add port number 1433 after the $ServerName$DatabaseInstanceName,1433.

After I added it, the exception became:

System.Data.SqlClient.SqlException: Login failed for user
‘domainname-PC$’

Then I found this link. It says to add Trusted_Connection=False;.

The whole connection string should be like:

data source=XXXXXSQLSERVER,1433;initial catalog=XXXDB;user id=UserID;password=PWD;Trusted_Connection=False;MultipleActiveResultSets=True;

Hope this answer will help the ones out off Generic exception:

Error: 26-Error Locating Server/Instance Specified

Источник

Добрый день!

Прошу помощи в решении следующей проблемы.

Есть корпоративная сеть из нескольких машин с разрядностью как 32, так и 64. Авторизация происходит по доменным учетным записям.

Установила на 64-разрядную машину 2 пользовательских инстанса SQL Server 2008 R2: один со смешанным режимом авторизации (пользователь sa), другой с проверкой подлинности Windows.

1. Sql Browser запущен.

2. TCP IP включен.

3. Брандмауэр windows Отключен.

4. В Sql Server Management Studio стоит галочка: allow remote connections.

Локально все подключается нормально. Второй 64-разрядный комп в сети также спокойно подключается к инстансам.
32-разрядные компы же выдают следующую
ошибку:

При установлении соединения с SQL Server произошла ошибка, связанная с сетью или с определенным экземпляром. Сервер не найден или недоступен. Убедитесь, что имя экземпляра указано правильно и что на SQL Server разрешены удаленные соединения. (provider:
SQL Network Interfaces, error: 26 — Ошибка при обнаружении указанного сервера или экземпляра)

Подскажите, в чем может быть проблема?

Источник

Methods to Resolve SQL Server Error 26

Users often see “SQL Network Interfaces, error: 26 – Error Locating Server/Instance Specified” error message while connecting to SQL Server. This error 26 SQL server is quite common nowadays as a lot of users are complaining about it.

SQL Server Error 26 occurs when users trying to connect to a SQL Server named instance. The reason of the SQL Server Error 26 is the client stack could not receive SSRP response UPD packet from SQL Browser. Now, there a few ways to solve SQL network interfaces error 26 in a smart way. Stay tuned to know the best way.

Table of Content

Quick Steps Guide

Windows Firewall Method

Other Causes of Error 26

Automated Solution

FAQs

Tip: Fix SQL Server Management Studio Error 40

SQL Error 26 Quick Solution in 5 Steps

Downlaod & Launch tool in your PC

Click on Open to Add database files

Select Quick or Advance Scan mode

Select Settings & Destination Location

Click on Export button to get your results

You have to create an incoming rule that allows traffic from all promising IP addresses that are configured for the failover cluster instance and from all possible IP addresses of the remote server. For this, just follow the below steps. We’re sure that this way users can easily get rid of this SQL network interfaces error 26 for sure.

- Open Adminstrative Tools, from Control Panel to begin solving error 26 SQL server
- In Adminstrative Tools, click on Windows Firewall with Advanced Security
- Under Windows Firewall with Advanced Security on Local Computer column, click on the Inbound Rule and then select New Rule from the right pane

- From New Inbound Rule Wizard window, select Custom and then click on the Next button

- Under Does this rule apply to all programs or a specific program? select All programs then click on Next button

- Form Protocol type list, select Any and then click on Next button

- Under Which remote OP addresses does this rule apply to? select These IP addresses and then click on Add button

- In IP Address dialog box, under This IP address or subnet type the IP address and then click on Ok button

- Under What action should be taken when a connection matches the specified conditions? select Allow the connection and then click on Next button

Click on the Next button to complete the New Outbound Rule Wizard steps

Other Possible Causes of SQL Server Error 26 with Solution

SQL Server does not allow remote connections

To resolve the SQL Server Error 26 open SQL Server Management Studio, Right click on the database and select properties
On Security page, select SQL Server and Windows Authentication mode and click on Ok button
Restart SQL Server

If you are still facing the Error 26, then there could be a same name conflict between two systems. Check whether the computer name, system name is same if yes, then try to system using its IP address. In addition this error 26 occurs with several issues that are mentioned below:

SQL network interfaces, error: 26 – error locating server/instance specified
provider: SQL network interfaces, error: 26 – error locating server/instance specified
a network related or instance specific error in SQL server error 26

Experts’ Recommended Solution to Counter Errors Causes Due to Corruption

Now when there is some sort of data corruption issues present in the server, the SQL database might react differently than what it should usually do. Therefore, experts often suggest users to get the automated repair & recovery tool.

Downlaod the tool & then follow easy steps to repair damaged data & solve SQL network interfaces error 26 with ease. In addition, if you want to know how to make SQL server faster then this tool can remove corruption as well. Ultimately resulting in a faster server.

Download Now Purchase Now

Step-1. Launch the Tool in your system & then Click the Open button.

Step-2. Select the Quick or Advanced Scan Mode as per your need.

Step-3. Set the SQL Server database details to continue further.

Step-4. Finally, Click on the Export button to finish the task.

Frequently Asked Questions

Q-1. What is connection error 26 in SQL Express?

A: It is crucial for users to ensure that the name of their server is correct & no typo on the name is present. Always make sure that your SQL browser service is running on the server in case you are trying to connect SQL instance on another server. Your machine should be reachable.

Q-2. How do I fix error code 26?

A: The device drivers of your system are closely connected to the error 26. Removing all external devices can be a solution too here.

Q-3. What is SQL Server error 26 client unable to establish connection because an error was encountered during handshakes before login?

A: The most common reason for this is when a client connects to a unsupported version of SQL Server. Here the the error occurs because the server is too busy to accept the new connections. In some cases, resource limitation is also an issue where maximum allowed connected are pre defined.

Q-4. How do I fix SQL query error?

A: There are 4 steps to fix SQL query error as mentioned below:

Navigate to the failing line in SQL query.
Check failing SQL syntax in SQL query.
Check query logic in joins, subqueries, or CTEs.
Go to troubleshooting error messages to finish.

Q-5. How to restart SQL Server?

A: Go to SQL Server Configuration Manager >> Select SQL Server Services, Right Click a named instance or SQL Server> Select from Start, Stop, Pause, Resume & Restart options.

Q-6. How do I allow remote access to SQL Server database?

A: 5 Steps to allow remote access to SQL Server database:

Start SSMS (SQL Server Management Studio)
Go to Object Explorer & Right Click on Server
Select Properties & then Click Connections
Enable Allow Remote Connections to this Server
Click on Ok to save & Finish the task.

Источник

Remove From My Forums

provider: SQL Network Interfaces, error: 26 — Error Locating Server/Instance Specified

Question

I used profile for shopping cart

Collapse

<system.web>
<anonymousIdentification enabled="true"/>
 <customErrors mode="Off"></customErrors>
 <profile enabled="true">
  <properties>
   <add name="SCart" serializeAs="Binary" type="Tandis.Cart" allowAnonymous="true"/>
  </properties>
 </profile>
</system.web>

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)

Source Error:





  


                       
  




Line 19:   public virtual Tandis.Cart SCart {
Line 20:     get {
Line 21:       return ((Tandis.Cart)(this.GetPropertyValue("SCart")));
Line 22:     }
Line 23:     set {

Source File: c:windowsMicrosoft.NETFrameworkv2.0.50727Temporary ASP.NET Filesroot2faf057937b1b4f4App_Code.1mhfv5r1.3.cs
Line: 21

Stack Trace:


[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: SQL Network Interfaces, error: 26 - Error Locating Server/Instance Specified)]
  System.Data.SqlClient.SqlInternalConnection.OnError(SqlException exception, Boolean breakConnection) +4849719
  System.Data.SqlClient.TdsParser.ThrowExceptionAndWarning(TdsParserStateObject stateObj) +194
  System.Data.SqlClient.TdsParser.Connect(ServerInfo serverInfo, SqlInternalConnectionTds connHandler, Boolean ignoreSniOpenTimeout, Int64 timerExpire, Boolean encrypt, Boolean trustServerCert, Boolean integratedSecurity, SqlConnection owningObject) +4863021
  System.Data.SqlClient.SqlInternalConnectionTds.AttemptOneLogin(ServerInfo serverInfo, String newPassword, Boolean ignoreSniOpenTimeout, Int64 timerExpire, SqlConnection owningObject) +90
  System.Data.SqlClient.SqlInternalConnectionTds.LoginNoFailover(String host, String newPassword, Boolean redirectedUserInstance, SqlConnection owningObject, SqlConnectionString connectionOptions, Int64 timerStart) +376
  System.Data.SqlClient.SqlInternalConnectionTds.OpenLoginEnlist(SqlConnection owningObject, SqlConnectionString connectionOptions, String newPassword, Boolean redirectedUserInstance) +221
  System.Data.SqlClient.SqlInternalConnectionTds..ctor(DbConnectionPoolIdentity identity, SqlConnectionString connectionOptions, Object providerInfo, String newPassword, SqlConnection owningObject, Boolean redirectedUserInstance) +189
  System.Data.SqlClient.SqlConnectionFactory.CreateConnection(DbConnectionOptions options, Object poolGroupProviderInfo, DbConnectionPool pool, DbConnection owningConnection) +4864151
  System.Data.ProviderBase.DbConnectionFactory.CreatePooledConnection(DbConnection owningConnection, DbConnectionPool pool, DbConnectionOptions options) +31
  System.Data.ProviderBase.DbConnectionPool.CreateObject(DbConnection owningObject) +433
  System.Data.ProviderBase.DbConnectionPool.UserCreateRequest(DbConnection owningObject) +66
  System.Data.ProviderBase.DbConnectionPool.GetConnection(DbConnection owningObject) +499
  System.Data.ProviderBase.DbConnectionFactory.GetConnection(DbConnection owningConnection) +65
  System.Data.ProviderBase.DbConnectionClosed.OpenConnection(DbConnection outerConnection, DbConnectionFactory connectionFactory) +117
  System.Data.SqlClient.SqlConnection.Open() +122
  System.Web.DataAccess.SqlConnectionHolder.Open(HttpContext context, Boolean revertImpersonate) +87
  System.Web.DataAccess.SqlConnectionHelper.GetConnection(String connectionString, Boolean revertImpersonation) +221
  System.Web.Profile.SqlProfileProvider.GetPropertyValuesFromDatabase(String userName, SettingsPropertyValueCollection svc) +772
  System.Web.Profile.SqlProfileProvider.GetPropertyValues(SettingsContext sc, SettingsPropertyCollection properties) +433
  System.Configuration.SettingsBase.GetPropertiesFromProvider(SettingsProvider provider) +258
  System.Configuration.SettingsBase.GetPropertyValueByName(String propertyName) +132
  System.Configuration.SettingsBase.get_Item(String propertyName) +102
  System.Web.Profile.ProfileBase.GetInternal(String propertyName) +36
  System.Web.Profile.ProfileBase.get_Item(String propertyName) +68
  System.Web.Profile.ProfileBase.GetPropertyValue(String propertyName) +7
  ProfileCommon.get_SCart() in c:windowsMicrosoft.NETFrameworkv2.0.50727Temporary ASP.NET Filesroot2faf057937b1b4f4App_Code.1mhfv5r1.3.cs:21
  Showbook.Button2_click(Object sender, EventArgs e) in c:inetpubvhoststandisbooks.irhttpdocsShowbook.aspx.cs:22
  System.Web.UI.WebControls.ImageButton.OnClick(ImageClickEventArgs e) +108
  System.Web.UI.WebControls.ImageButton.RaisePostBackEvent(String eventArgument) +118
  System.Web.UI.WebControls.ImageButton.System.Web.UI.IPostBackEventHandler.RaisePostBackEvent(String eventArgument) +10
  System.Web.UI.Page.RaisePostBackEvent(IPostBackEventHandler sourceControl, String eventArgument) +13
  System.Web.UI.Page.RaisePostBackEvent(NameValueCollection postData) +36
  System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint) +1565

Version Information: Microsoft .NET Framework Version:2.0.50727.4206; ASP.NET Version:2.0.50727.4209

it works locally on IIS but on the host it gives this error!
what should I do ? (my host is plesk 9.5 )

Answers

Hi Nima,

Thank you for your post.

The reasons for throwing this issue could be wrong server name, disabled remote connection

and firewall blocking.

Could you please follow the steps below to solve this issue?

·         Check the server on which SQL Server is running can be accessible. You can use ping command to test that. For instance, ping <computer_name> or ping <IP_address>.
The ping command may be block by the firewall, make sure ICMP is enabled in the firewall. More info, check:

http://technet.microsoft.com/en-us/library/cc739791%28v=ws.10%29.aspx#BKMK_4.

·         Choose appropriate protocol

·         Configure Windows firewall accordingly based on what protocol you have chosen to use. For detailed information about how to configure Windows Firewall to allow SQL Server,
please check http://msdn.microsoft.com/en-us/library/cc646023.aspx.

·         Enable SQL Server Browser Services

You need to enable SQL Server Browser Services if the following are both true:

1.       SQL Server is not listening on default 1433 port or not use default pipe name
\.pipesqlquery;

2.       The corresponding TCP port or pipe name is not specified in the connection string (such as Srv1SQL2008, 1500).

If you have enabled SQL Server Browser Services, you still need to open UDP 1434 port which is used by Browser Services in the Windows firewall.

Best Regards,
Peja Tao

Please remember to click «Mark as Answer» on the post that helps you, and to click «Unmark as Answer» if a marked post does not actually answer your question. This can be beneficial to other community members reading the thread.
- Proposed as answer by
  
  Friday, March 18, 2011 6:36 AM
- Marked as answer by
  Alex Feng (SQL)
  Friday, March 25, 2011 4:19 AM

Источник

Okay so a lot of people have posted a similar question, however I don’t seem to be able to find a solution to my problem in any of them. So this is my situation.

Yesterday I was working with my SQL Server Express through SQL Server Management Studio. I close my projects as I’ve done multiple times before and then this morning when I tried to connect again with the tool is gives me this error:

TITLE: Connect to Server

Cannot connect to .SQLExpress.

ADDITIONAL INFORMATION:

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) (Microsoft SQL Server, Error: -1)

I think my main question here is if there is a solution to this problem, or if I have to install SQL Server Express all over again?

PS: Here are some system stats. I’m working on a Windows 10 machine, and the SQL Server Management Studio version is 2014.

Источник

When you try to connect to a local instance, SQL Server will always attempt to use Shared Memory. This connection will work fine:

localhostSQL2012

This works in my scenario, and the connection is indeed using Shared Memory in this case.

SELECT session_id,net_transport,local_net_address,local_tcp_port
FROM sys.dm_exec_connections;

Results:

session_id  net_transport   local_net_address   local_tcp_port
----------  -------------   -----------------   --------------
53          Shared memory   <local machine>     NULL

If you want to try to override Shared Memory (not sure why, on a local machine) and force TCP/IP instead, you can’t mix that with specifying the named instance explicitly, at least in all instances I tried (no pun intended). The named instance forces SQL Server to map the instance name to the port number, using SQL Server browser, but this apparently can’t be done when you force TCP/IP in the first place (the whole point of using TCP/IP is so you go straight to the port and not bother with the browser). If your named instance happens to be running on its own IP address and forced to port 1433, you may be able to get this to work; you may also be able to get it to work if you are using a Client Network alias (but I could not).

I was able to connect if I looked up the current dynamic port assigned to that instance in Configuration Manager (in my case it was 49538), and then connect using tcp:localhost,49538:

So now:

SELECT session_id,net_transport,local_net_address,local_tcp_port
FROM sys.dm_exec_connections;

Results:

session_id  net_transport   local_net_address   local_tcp_port
----------  -------------   -----------------   --------------
53          Shared memory   <local machine>     NULL
54          TCP             10.211.55.10        49538

All variations I tried — across multiple machines and versions — where I tried to combine a named instance with overriding shared memory and use TCP/IP instead — yielded the same error that you received. This is both when I prefixed the server/instance name with tcp: and when I specified TCP/IP for the network protocol in the connection properties dialog.

Long story short: If you really need to force TCP/IP for a local connection, you’re going to need to use a fixed port for that instance, and specify the port. Or use 1433 (which will only work if there’s no default instance or if you have a dedicated IP address for that instance), then you won’t need to specify the port, but you’ll still need to specify the tcp: prefix or use that option in the connection dialog.

I do not suggest trying to disable Shared Memory. FWIW.

Источник

Methods to Resolve SQL Server Error 26

Table of Content

Quick Steps Guide

Windows Firewall Method

Other Causes of Error 26

Automated Solution

FAQs

Tip: Fix SQL Server Management Studio Error 40

SQL Error 26 Quick Solution in 5 Steps

Downlaod & Launch tool in your PC

Click on Open to Add database files

Select Quick or Advance Scan mode

Select Settings & Destination Location

Click on Export button to get your results

- Open Adminstrative Tools, from Control Panel to begin solving error 26 SQL server
- In Adminstrative Tools, click on Windows Firewall with Advanced Security
- Under Windows Firewall with Advanced Security on Local Computer column, click on the Inbound Rule and then select New Rule from the right pane

- From New Inbound Rule Wizard window, select Custom and then click on the Next button

- Under Does this rule apply to all programs or a specific program? select All programs then click on Next button

- Form Protocol type list, select Any and then click on Next button

- Under Which remote OP addresses does this rule apply to? select These IP addresses and then click on Add button

- In IP Address dialog box, under This IP address or subnet type the IP address and then click on Ok button

- Under What action should be taken when a connection matches the specified conditions? select Allow the connection and then click on Next button

Click on the Next button to complete the New Outbound Rule Wizard steps

Other Possible Causes of SQL Server Error 26 with Solution

SQL Server does not allow remote connections

To resolve the SQL Server Error 26 open SQL Server Management Studio, Right click on the database and select properties
On Security page, select SQL Server and Windows Authentication mode and click on Ok button
Restart SQL Server

SQL network interfaces, error: 26 – error locating server/instance specified
provider: SQL network interfaces, error: 26 – error locating server/instance specified
a network related or instance specific error in SQL server error 26

Experts’ Recommended Solution to Counter Errors Causes Due to Corruption

Download Now Purchase Now

Step-1. Launch the Tool in your system & then Click the Open button.

Step-2. Select the Quick or Advanced Scan Mode as per your need.

Step-3. Set the SQL Server database details to continue further.

Step-4. Finally, Click on the Export button to finish the task.

Frequently Asked Questions

Q-1. What is connection error 26 in SQL Express?

Q-2. How do I fix error code 26?

A: The device drivers of your system are closely connected to the error 26. Removing all external devices can be a solution too here.

Q-3. What is SQL Server error 26 client unable to establish connection because an error was encountered during handshakes before login?

Q-4. How do I fix SQL query error?

A: There are 4 steps to fix SQL query error as mentioned below:

Navigate to the failing line in SQL query.
Check failing SQL syntax in SQL query.
Check query logic in joins, subqueries, or CTEs.
Go to troubleshooting error messages to finish.

Q-5. How to restart SQL Server?

A: Go to SQL Server Configuration Manager >> Select SQL Server Services, Right Click a named instance or SQL Server> Select from Start, Stop, Pause, Resume & Restart options.

Q-6. How do I allow remote access to SQL Server database?

A: 5 Steps to allow remote access to SQL Server database:

Start SSMS (SQL Server Management Studio)
Go to Object Explorer & Right Click on Server
Select Properties & then Click Connections
Enable Allow Remote Connections to this Server
Click on Ok to save & Finish the task.

Добрый день!

Прошу помощи в решении следующей проблемы.

1. Sql Browser запущен.

2. TCP IP включен.

3. Брандмауэр windows Отключен.

4. В Sql Server Management Studio стоит галочка: allow remote connections.

Подскажите, в чем может быть проблема?

SQL Server Error 26 and SQL Server Error 40 appear when you try to connect to SQL Server. We will troubleshoot and try to fix them in the same article as both are related to connection issue. We recommend to use the below solutions for the both errors and to try to localize the problem.

The error Messages:

(provider: SQL Network Interfaces, error: 26 – Error Locating Server/Instance 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: 26 – Error Locating Server/Instance Specified)

“ Named Pipes Provider Error: 40 – Could not open a connection to SQL Server“.

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)

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 the SQL Server is configured to allow remote connections. (provided: Named Pipes Provider, error: 40- Could not open a connection to the SQL Server) (Microsoft SQL Server, Error: 2).

sql server error 26

What is SQL Server Error 26?

You will get this error message while trying to connect to a SQL Server named instance and not when you use default instance. The client stack could not receive SSRP response UDP packet from SQL Browser.

How to fix Error 26 on SQL Server?

Recheck the server name for any error and fix it
Check the instance name for any error
Check if SQL Server browser is running
Control if this instance exist on server
Ping the server and check if DNS can be resolved correctly

What is SQL Server Error 40?

This error appears mostly when SQL Server does not allow remote connections, Firewall Settings or TCP/IP is not enabled. We will explain below all those in order to troubleshoot easy.

Read also other SQL Server Helping Posts:

How to fix SQL Server Error 229
Fix SQL Server Error 233
SQL Server Error 17002

How to fix error 40 on SQL Server?

Check SQL Server is running
Make sure that Allow Remote Connections is enabled on sql server properties
Check if TCP/IP is enabled
Configure to allow SQL Server in Firewall Settings
Check for working fine SQL Server Browser
Make sure that you can ping the SQL Server

Below we will explain the above steps in long way for better understanding and easy fix of SQL error 26 and sql error 40.

1. Check if SQL Services are running

Hint! If you are running SQL Server by using an instance name and you are not using a specific TCP/IP port number in your connection string, you must enable the SQL Server Browser service to allow for remote connections.

How to check if SQL Server Service is running?

Go to SQL Server Configuration Manager > SQL Server Services
Find the service SQL Server (MSSQLSERVER) if default or the name of your instance
Check if is running – should be running state with a green indication

Using Windows Command Prompt

sc query mssqlserver

For named instance name use below by by replacing instancename with the actual SQL Server instance name.

sc query mssql$instancename

How to check if SQL Server Browser is running?

Navigate to SQL Server Configuration Manager > SQL Server Services
Find the SQL Server Browser Service
Check if it is configured to start automatically and is started – should be with a green indication

Using Windows Command Prompt

sc query sqlbrowser

Check if SQL Server Service

2. Try to Flush DNS

How to flush DNS?

Click Start Button
Type CMD and press enter
Type this into the black window that appears: ipconfig /flushdns and press enter.

Fluish DNS

3. Make sure that allow Remote Connection is enabled

Check if remote connections is allowed for applications/client. This option need to be allowed to establish connections and perform operations on the server. Often this is the reason of SQL Server Error 26 and SQL Server Error 40.

How to check if the remote connection is enabled?

Open ‘SQL Server Management Studio’
Right click on database name and select ‘Properties’
In ‘Properties’ window, select ‘Security’, enable `SQL Server and Windows Authentication mode` and click `OK`.
Now restart the SQL server.

Allow Remote Connections

4. Check Firewall

Check the firewall status for any troubles:

Open ‘Control Panel’ and after that ‘Windows Firewall’.
Select ‘Change Settings’ In ‘Windows Firewall’,
Add an exception for port ‘1434’ and name it ‘SQL Server’
Enable by clicking on the checkbox

5. Connection String

This solution is on cases when you are using connection string and are you writing it wrongly. For example connection string used by .NET framework:

Server=serverAddress;Database=dbName;User Id=username;

Password=password;

Check for each parameter passed in the connection string for any typographical errors.
Control the validity of the username/password.
Confirm if the given database exists.

6. TCPIP Protocol

This solutions can work when you have mix of default and named instance or named instances only.

How to Enable TCP/IP port?

Open SQL Server Configuration Manager
Click on SQL Server Network Configuration and click on Protocols for Name
Right-click on TCP/IP
Click Enable
Restart your SQL Server instance

Enable TCP-Ip port

If you want to use a static port for your instance (instead of dynamic that changes after every restart) you can change it here.

Open Properties for TCP/IP protocol
Go to IP Addresses tab
Scroll down to IPAll section
Remove 0 value from TCP Dynamic Ports
Specify your port in TCP Port

You can use this port to connect to your instance by providing <servername>,<port> or <IP>,<port> as Server Name (yes, there is a comma, not a colon).

TCP-Ip static port

Conclusion:

We have explained some solutions to fix SQL Server Error 26 and SQL Server Error 40 and hope that you find the fix on those solutions. The both errors are included on the same article because they have almost the same troubleshoot. If you have any other solution worked for you comment below and we will try to include it on our article.

Источник

Methods to Resolve SQL Server Error 26

SQL Error 26 Quick Solution in 5 Steps

Other Possible Causes of SQL Server Error 26 with Solution

Experts’ Recommended Solution to Counter Errors Causes Due to Corruption

Frequently Asked Questions

<img itemprop="url image" decoding="async" src="https://i1.social.s-msft.com/globalresources/Images/trans.gif?cver=0001" alt=" locked" /> provider: SQL Network Interfaces, error: 26 — Error Locating Server/Instance Specified

Question

Server Error in ‘/’ Application.

Answers

Methods to Resolve SQL Server Error 26

SQL Error 26 Quick Solution in 5 Steps

Other Possible Causes of SQL Server Error 26 with Solution

Experts’ Recommended Solution to Counter Errors Causes Due to Corruption

Frequently Asked Questions

1. Check if SQL Services are running

2. Try to Flush DNS

3. Make sure that allow Remote Connection is enabled

4. Check Firewall

5. Connection String

6. TCPIP Protocol

Conclusion:

provider: SQL Network Interfaces, error: 26 — Error Locating Server/Instance Specified