Clik here to view.
SQL Network Interfaces, error: 26 - Error Locating Server/Instance Specified
Users often see this error message when connection to a SQL Server and don't know where to start to solve the problem. In most forums, people says this is because remote connection is not enabled on...
View ArticleClik here to view.
Named Pipes Provider, error: 40 - Could not open a connection to SQL Server...
This error message is the most frequent error message when connecting to SQL Server. You see this error message when you use SqlClient. In SNAC, the error message is slightly differently as follows:...
View ArticleClik here to view.
Connecting to SQL Server 2005 on Vista and Longhorn
Some customers have experienced problems connecting to SQL Server 2005 on Vista and Longhorn. Even though they are trying to connect using an account that is an administrator on the box, they get a...
View ArticleClik here to view.
Install a self-signed test certificate that can be loaded by SQL Server...
In the blog Certificate for SQL Server 2005, I explained the requirements of a certificate for SQL Server 2005. Customer usually needs to purchase a certificate from certificate authorities (such as...
View ArticleClik here to view.
SSL Cipher Suites used with SQL Server
When enabling channel encryption between the application and SQL Server, users may wonder what encryption algorithm is being used to protect their data. Unfortunately, this isn't an easy question to...
View ArticleClik here to view.
Login failed for user , Msg 18456, Level 14, State 1
This post focus on a typical cause of sql login failure issue described as the title. In real world, a customer log on to the machine as a domain\user or local machine accout, he can connec to SQL...
View ArticleClik here to view.
TCP Provider: No connection could be made because the target machine actively...
In this post, I am trying to list out potential cause and general solution to this specific error when you are making connection to SQL Server 2005. First, It is due to TCP connection fail, since you...
View ArticleClik here to view.
Service Principal Name (SPN)
Did you know that beginning with SQL Server 2008, support for service principal names (SPNs) has been extended to enable mutual authentication across all protocols. Administators can now define their...
View ArticleClik here to view.
Why Browser is installed under 90\shared directory rathar than 100\Shared?
After installing SQL Server 2008, some users might notice that sqlbrowser.exe is installed under %ProgramFiles%Microsoft SQL Server\90\Shared, rather than %ProgramFiles%Microsoft SQL Server\100\Shared...
View ArticleClik here to view.
Understanding “Connection forcibly closed by remote host” Errors Caused by...
Sporadic “Connection forcibly closed by remote host” errors with SQL Server connections can be very difficult to troubleshoot and resolve. This blog post is targeted at diagnosing TOE/Chimney issues...
View ArticleClik here to view.
Could not connect to X64 named instance
We see a couple of cases where customer could not connect to named instance on X64. They all have the following symptons. 1) Customer has no problem to connect X86 instance on the same server machine...
View ArticleClik here to view.
Steps to troubleshoot SQL connectivity issues
We have been seeing and trying to resolve SQL connectivity issue all the time. I guess it would be helpful if we can put some guidance on how to resolve connectivity issues. Here comes a proposal based...
View ArticleClik here to view.
Understanding the error message: “Login failed for user ''. The user is not...
Understanding the error message: “Login failed for user ''. The user is not associated with a trusted SQL Server connection.” This exact Login Failed error, with the empty string for the user name, has...
View ArticleClik here to view.
Connectivity troubleshooting in SQL Server 2008 with the Connectivity Ring...
SQL Server 2008 contains a new feature designed to help troubleshoot particularly tricky connectivity problems. This new feature, the Connectivity Ring Buffer, captures a record for each...
View ArticleClik here to view.
Troubleshooting SQL Server Cluster Installations
On a Windows Cluster it is possible to install a SQL Server Cluster, which will be a separate entity with disctinct Virtual Server Name, IP address, and pipe name. The nodes of the SQL Cluster must be...
View ArticleClik here to view.
Connection failure because of mismatched TDS version
Some customers have reported connection failure because of wrong TDS version. The client application gets the following error message: (or similar depends on the protocol used) A connection was...
View ArticleClik here to view.
Configuring SQL Protocols through Windows PowerShell
Sometimes we are asked about the possibility of configuring SQL Server protocols through PowerShell. In SQL Server 2008, the sqlps tool incorporates WMI and SMO into this powerful...
View ArticleClik here to view.
Understanding “Data Source=(local)” in SQL Server Connection Strings
Lately we have noticed many misunderstandings surrounding the usage of the Data Source keyword in connection strings, caused by people generalizing from an example demonstrating a connection string for...
View ArticleClik here to view.
TCP listening ports and ENDPOINT ports behavior
Endpoint configuration seems to be creating some confusion. I hope that this will clarify some of the behavior as it applies to TCP endpoints. With a default configuration of SQL Server, try the...
View ArticleClik here to view.
Understanding the error “An operation on a socket could not be performed...
This error message, which is associated with the Winsock error WSAENOBUFS and actually comes from Windows rather than SQL Server directly, has two well-understood root causes. However, it still stumps...
View Article
