Installing Arbortext Publishing Engine > Installation Overview > Upgrading from a Previous Release of Arbortext Publishing Engine
  
Upgrading from a Previous Release of Arbortext Publishing Engine
During an installation, you should be logged on with Administrator privileges to ensure proper removal of all previous Arbortext Publishing Engine files and registry entries. If the web server or servlet container are running, you need to stop them before upgrading to release the Arbortext Publishing Engine files that may be in use.
You should check the directories for files that you may have customized in case you want to save them to reuse with your upgraded release.
• Look for custom files in the PE_HOME\custom subdirectory structure. The uninstall feature leaves your custom files in the custom directory intact. You can reuse the previous install path if you have files in the custom directory.
• The installation overwrites any existing file having the same name and path. If you placed custom files in other install tree locations, be sure to make backup copies of them as the installation could overwrite them.
• Be sure to save a copy of your current PE_HOME\e3\e3\WEB-INF\e3config.xml file with your configuration settings to a backup location. After you finish the installation, you can migrate your configuration settings to the new e3config.xml file.
License Upgrade
You will need to obtain a new license for the Arbortext Publishing Engine 7.1 release. You must update your license each time you upgrade to a major Arbortext Publishing Engine F000 release (maintenance releases or datecode updates would not require a license update). For example, a license issued for 7.1 would work with Arbortext Publishing Engine 7.1 M010. A license issued for 7.0 would not be compatible with 7.1, 7.2 and so on.
Licenses issued for previous releases (such as 7.0) will not work with Arbortext Publishing Engine 7.1.
The license information is stored in the PTC_D_LICENSE_FILE environment variable. If it does not exist or has an incorrect value, a license error will be reported. See Arbortext Publishing Engine Licensing for instructions on obtaining and installing a license.