Hi, I am using logback for my application and find one more issue. I am not sure it's bug or I need to write my own class to overwrite the existing class. I try to generate CSV file from my application and using fileHeader for the output. 1. It's working fine for first time, when log file is not existing. I have not try rollover yet, but I think it's fine as well. The head is on the first line of the file. <encoder class="ch.qos.logback.core.encoder.LayoutWrappingEncoder"> <layout class="ch.qos.logback.classic.PatternLayout"> <fileHeader>Time current max percentage</fileHeader> <pattern>%m%n</pattern> </layout> </encoder> 2. question is when I restart my app, the log file exists there. The fileheader is append , this make the file has two head lines. Because the property called "fileHeader", I thought only one header for one file. So is this a bug? or I have to implement my own class to overwrite LayoutWrappingEncoder or PatternLayout classes. Thanks Kevin ------------------------------------------------------------------------------ Confidentiality notice: This email may contain information that is confidential or legally privileged. If you have received it by mistake, please: (1) reply promptly to that effect, and remove this email and the reply from your system; (2) do not act on this email in any other way. Thank you. ------------------------------------------------------------------------------