Hi, I tried to use PatternLayout in my application, by mimicking the code in the Chapter 5 of the manual (http://logback.qos.ch/manual/layouts.html#ClassicPatternLayout) and kept getting this kind of errors : %PARSER_ERROR_message%PARSER_ERROR_n I ended up trying to compile the exact same code as in the manual and in the PatternSample.java example, still getting the same output. Looking into the sources gave me the idea to set the context of the layout, which indeed solved the problem : PatternLayout layout = new PatternLayout(); layout.setContext(rootLogger.getLoggerContext()); // <= ADDED THIS LINE layout.setPattern("%-5level [%thread]: %message%n"); layout.start(); Before that, I searched a solution to this problem on the net and didn't find anything relating to it, so I figured I should leave a message here in case it can help others... I don't know if the problem originates from a bug in logback or a mistake in the manual, so I post in the user list. I think it should get fixed, at least in the manual, though. Cheers, Éric