Basic Customization > Windchill Customization Basics > Managing Customizations > Setting Up a Directory Structure for Managing Customized Files and Text Tailoring
  
Setting Up a Directory Structure for Managing Customized Files and Text Tailoring
To customize a Windchill system it is often necessary to modify files released by PTC. Because these files can subsequently be updated by PTC in a maintenance release, you should use a strategy for managing your files so that your customizations are not lost when the maintenance updates are installed.
As a general rule, the Windchill Service Pack installer can overwrite any files that are in established PTC directories under the installation directory where the Windchill product is installed, regardless of their modification status. It is your responsibility to manage your customized files to avoid loss of your changes and, when updates are applied, to be able to easily identify PTC changes that affect the files you have modified.
PTC recommends that you manage customized files by creating a directory structure known as the safe area. The actual directory name is <Windchill>/wtSafeArea, where <Windchill> is the directory where Windchill Services is installed. By using the wtSafeArea directory, you can store copies of the customized versions of PTC files where they will not be overwritten by the Windchill Service Pack installer, as well as keep versions of the original PTC files. Additionally, the Windchill Service Pack installer uses this safe area to store updated files that correspond to your customized files. You can then compare the original files to those updated by PTC to identify where changes have been made. Doing the comparison can assist you in incorporating PTC updates into your customized files. PTC provides a script to assist with managing and installing customized files into your system runtime locations within the <Windchill> installation directory.
Additionally, if you make changes to resource bundle information files (RBINFO files), then you must use the <Windchill>/wtCustom directory structure to store those changes.