Hello, I have this piece of code: http://pastebin.com/iMyyaB6a It adds a file and a console log and reads in a file config: [Core] # Filter="%Severity% > 1" [Sinks.MyConsoleSink1] Destination=Console and prints some messages: using namespace boost::log::trivial; boost::log::sources::severity_logger<severity_level> lg; BOOST_LOG_SEV(lg, trace) << "A trace severity message"; BOOST_LOG_SEV(lg, debug) << "A debug severity message"; BOOST_LOG_SEV(lg, info) << "An informational severity message"; BOOST_LOG_SEV(lg, warning) << "A warning severity message"; BOOST_LOG_SEV(lg, error) << "An error severity message"; BOOST_LOG_SEV(lg, fatal) << "A fatal severity message"; It does exactly what I want, prints each message twice to the console. But when I uncomment the Filter expression it prints nothing. Why not? Severity > 1 means everything info and above, doesn't it? Thanks, Florian