Hi,
I use VFP to SQL Server all the time and know most of the issues with allowing Remote Connections. However, I now have an ASP.NET C# website that uses SQL Server Express and works fine on my development machine and also worked fine on the clients standalone server. They added the standalone server to their domain and now the site fails with the error:

[SqlException (0x80131904): 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)]

I didn't think that remote connections would be involved here as the site, IIS and SQL Server all sit on the same machine but I have ensured that everything is configured properly: the database allows remote connections, TCP/IP is enabled and the Dynamic Ports is bank with the TCP port set to 1433. The only thing I haven't done is check the Firewall to ensure 1433 is accessible, but as it's the same machine, shouldn't this be unnecessary?

Any ideas as to how to what could be going on here?