Hi @Rahul Gollapalli ,
Welcome to Q&A Forum!
Please perform the following troubleshooting:
1.Make sure the SQL Server and SQL Server Browser services are running at all times on the server hosting your SQL instance.
2.Check and disable Windows Firewall on the SQL Server
Here are a few good blogs that might help you:
- 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.
- How to Fix the Error ‘A Network-related or Instance-specific Error occurred while Establishing a Connection to SQL Server’ ?
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