Note for developers: Apps affected by this issue might fail to fetch data, for example when using the SQLFetch function. You might receive an error within the app or you might receive an error from SQL Server, such as 'The EMS System encountered a problem' with 'Message: Protocol error in TDS Stream' or 'Message: Unknown token received from SQL Server'. Database connections using Microsoft ODBC SQL Server driver might fail.Īfter installing KB5019959, apps which use ODBC connections utilizing the Microsoft ODBC SQL Server Driver (sqlsrv32.dll) to access databases might fail to connect.