我的应用程序不使用SQL Server Express，但它正在寻找App_Data中的数据库 - 为什么？

Question

My application uses SSRS (on SQL Server 2017 on a server) and IIS. It runs fine in my IDE (VS 2017 or VS 2015) but when I put it on the server I get an error page.

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)

No connection string to SQL Server Express.

Answer 1

• Firstly make sure that your SQL server is running and SQL Server browser service is running.
  • Make sure SQL Server is configured to allow remote connections.
  • Examine the SQL Server error log for messages confirming that SQL is listening on the expected network interfaces and ports.
  • Test server connectivity with PING from the client machine.
  • Test port connectivity using TELNET or PowerShell to the server and port from the client machine. For example a. TELNET 1433 b. PowerShell: 1433 | % { echo ((new-object Net.Sockets.TcpClient).Connect("YourServerName",$ )) "server listening on TCP port $ " }
  • Check firewall settings.
  • Also check your web.config file.

You could also refer below article: “A network-related or instance-specific error occurred”

Regards, Jalpa.