Unable to connect to the Always On HA database group on the SQL server

After you update NPM to version 12.2, the Configuration Wizard fails when it connects to the Always On SQL Server Availability Group. When the Configuration Wizard fails, the following error message displays: 

WARN  MessageBusTopologyProvider - Could not load updated message bus host list from database.
System.Data.SqlClient.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: TCP Provider, error: 0 - The remote computer refused the network connection.) ---> System.ComponentModel.Win32Exception (0x80004005): The remote computer refused the network connection
   at System.Data.SqlClient.SqlInternalConnectionTds..ctor(DbConnectionPoolIdentity identity, SqlConnectionString connectionOptions, SqlCredential credential, Object providerInfo, String newPassword, SecureString newSecurePassword, Boolean redirectedUserInstance, SqlConnectionString userConnectionOptions, SessionData reconnectSessionData, DbConnectionPool pool, String accessToken, Boolean applyTransientFaultHandling)
   at System.Data.SqlClient.SqlConnectionFactory.CreateConnection(DbConnectionOptions options, DbConnectionPoolKey poolKey, Object poolGroupProviderInfo, DbConnectionPool pool, DbConnection owningConnection, DbConnectionOptions userOptions)
   at System.Data.ProviderBase.DbConnectionFactory.CreatePooledConnection(DbConnectionPool pool, DbConnection owningObject, DbConnectionOptions options, DbConnectionPoolKey poolKey, DbConnectionOptions userOptions)
   at System.Data.ProviderBase.DbConnectionPool.CreateObject(DbConnection owningObject, DbConnectionOptions userOptions, DbConnectionInternal oldConnection)
   at System.Data.ProviderBase.DbConnectionPool.UserCreateRequest(DbConnection owningObject, DbConnectionOptions userOptions, DbConnectionInternal oldConnection)
   at System.Data.ProviderBase.DbConnectionPool.TryGetConnection(DbConnection owningObject, UInt32 waitForMultipleObjectsTimeout, Boolean allowCreate, Boolean onlyOneCheckConnection, DbConnectionOptions userOptions, DbConnectionInternal& connection)

Additionally, when you re-run the Configuration Wizard, it resets the connection details as if caching is occurring.

Below is a troubleshooting summary:

• Set the SQL Configuration Manager to have the IP communicating to Enabled: Yes, Active: Yes
• Restart the SQL services.
• In the Configuration Wizard, insert SQL\Instance
• Configuration Wizard will fail with error: 0 - The remote computer refused the network connection.
• Checked the SWNetPerfMonDB file, It updates the connection string without the SQL instance name.
• Manually updated the SWNetPerfMon.DB file to SQL\Instance.
• Ran the configuration wizard, but it failed and reverted back to the connection string without SQL instance name.
• Cut SWNetPerfMonDB to desktop, re-ran wizard to recreate it from template. 

The customer configured a different name for their listener name than the group name.

• Follow the instructions in the Microsoft article View Availability Group Listener Properties (SQL Server) (© 2018 Microsoft, available at http://www.microsoft.com, obtained on November 29, 2018) and use the correct name.
• In most cases use only CLUSTER_NAME_OR_IP, PORT (Always On Availability Group is bound to the port, is not the instance).

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