I cannot connect to my local SQL Server Express (2012, but the version shouldn't matter) from my server (Windows 2008 R2) to use a tool on it (APEX SQL Data Diff if you are wondering). I can browse the network servers fine, and select my local instance from the dropdown of available servers, but when I go to search tables on the server, it times out with this error message (same is true of SSMS).
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: 28 - Server doesn't support strong text requested protocol) (Microsoft SQL Server, Error: -1)
I have enabled the firewall - that's not it.
I have allowed remote connections - that's not it.
SQL Server Browser service is on and passed through the firewall - that's not it.
I can connect fine with the same tools TO the server, but FROM the server it fails.