If the LiteSpeed application is on a separate client, a network IPC, such as TCP/IP or Named Pipes, is used to communicate with SQL Server. The SQL Server May be unreachable and you may get errors like "SQL Server does not exist or access denied" or "General Network Error." In some cases you can also get the error "Cannot Generate SSPI Context." if the configuration is incorrect.
1. Verify that SQL Server is listening on the correct IP address
2. Check for any aliases set for the SQL Server in the SQL Client Network Utility. Make sure the appropriate protocols are enabled on the client. LiteSpeed recommends Named Pipes first, and TCP/IP second. Verify that the designated port is not blocked.
3. Component Checker is a tool to verify the MDAC installation on that machine. In order to connect to named instances, clients would need to have MDAC 2.6 or later installed.
4. Use the SQL Server Network Utility to verify SQL Server's protocol settings and change properties, such as which protocols can connect to SQL Server and which ports are used.
5. Errors such as "Login failed for user 'user1'" or Login failed for user 'NTAUTHORITY\ANONYMOUS LOGON' Or "Login failed for user 'null'.", which don't mention a specific SQL Server login name, usually indicate a problem with Windows Authentication. In such cases you can use SQL Authentication to connect to SQL as a workaround, until you resolve the Windows Authentication issue.
6. If your connection fails with an error for a SQL Login, for example, "Login failed for user 'sa'. Not associated with a trusted connection," then verify that SQL Server is set up for Windows and SQL Authentication
If the connectivity issue is still unresolved, Network Monitor Trace may be a useful tool to obtain additional information.
All versions of LiteSpeed
All versions of SQL Server