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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...
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 1433
If 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.