SQL error code 53 generally indicates that the SQL Server being accessed is not found or is unreachable. This could happen due to the following reasons:
1. Network connectivity issues.
2. SQL Server instance is not running.
3. The SQL Server instance is not configured to accept remote connections.
To troubleshoot and resolve this error, you can try the following steps:
1. Verify network connectivity: - Check if you can ping the SQL Server machine from the computer where the query is being executed. - Verify that the SQL Server machine is running and accessible on the network.
2. Check if the SQL Server instance is running: - Connect to the SQL Server machine and ensure that the SQL Server service is running. - If not, start the SQL Server service.
3. Enable remote connections on the SQL Server: - Open SQL Server Configuration Manager. - Go to SQL Server Network Configuration > Protocols for [ServerInstance]. - Enable TCP/IP protocol and ensure it is enabled for remote connections. - Restart the SQL Server service.
If the error persists after following these steps, it may indicate a more specific issue. It would be helpful to provide additional details or error messages to assist with further troubleshooting.