In the Eclipse workspace, the log4j properties file is overwritten when you modify a WebApp project.
This issue occurs because the files from the WPFDesigner\\FeatureSets\\Web- App_X.X.X\\Templates\\Project
project template folder, overwrite the eclipse project files.
The following ways prevent overwriting the file:
Modify the log4j.properties file in the Templates\\Project folder.In Project Wizard
Select No when the Project Modify Wizard asks you if you wish to overwrite the file (log4j.properties). This approach is the easiest way to preserve the log4j.properties file settings.
Parent topic: Logging application behavior: wpf7