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Need help with SQL error 26
Hi All, I need help with SQL server error 26, I have a desktop application that runs on Windows Server and the app could be open on some servers and not others, attached image is the error that I get and I confirmed there is no firewall block as I could ping the SQL server and also remote desktop into it, can anyone advise me on this, thanks.
2 Replies
Ping and remoting are not sufficient to claim that there's no firewall issue between your client and the SQL Server.
By default, SQL Server is listening on TCP1433 (unless you have a named instance, in which case it's dynamic).The following powershell cmdlet will let you test the default port.
Test-NetConnection -Computername SqlServer -Port 1433If you're using named instances, that is "sqlserver\instancename", the communication starts with UDP1434 to the SQL Browser service.
The SQL Browser service then informs the client of the port used by the named instance, which the client then attempts to connect to.
AyushBansalMicrosoft
Hi tchia599 ,
To troubleshoot this, we will need more information on how this application is trying to connect to SQL Server. What is the connection string used by the application? Is it pointing to the correct SQL Server instance?
You can follow this troubleshooting workflow to isolate the issue: 0200 Consistent Network Issue · microsoft/CSS_SQL_Networking_Tools Wiki · GitHub
