Unknown SQL Exception 87 occurred. Additional error information from SQL Server is included below. Event ID: 5586 for SharePoint

If your SharePoint stops working and it throws ASP.NET yellow error screen and you find error in event viewer with EventID : 5586, it means your SharePoint virtual machines are unable to connect with SQL Server.

Here is detail of error.

“Event ID: 5586

Source: SharePoint Foundation (Microsoft-SharePoint Products-SharePoint Foundation)

Unknown SQL Exception 87 occurred. Additional error information from SQL Server is included below.

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: 25 - Connection string is not valid)”

To fix this issue, follow the steps.

1. Open SQL Server Configuration Manager, expand SQL Server Network Configuration and select protocols for your SQL instance.

2. Right click on TCP/IP, disable it and enable it again.

3. Select SQL Server Services and restart SQL Server service for your instance. If you are running SQL Server cluster, then restart SQL Server service from there.

4. Finally, restart all your SharePoint machines.

Once, SharePoint machines will come back, SharePoint will be back on track.

Thanks to my friend Adnan Khan for help finding the solution.

Happy SharePointing!