Installation Guide > Software Upgrade Preparation > Migrating Customizations
  
Migrating Customizations
If your current installation has been customized using environment variables or custom scripts or applications, you will need to migrate these customizations to this version of Arbortext Editor. It is recommended that you first install Arbortext Editor on a test system reflecting your current user environment. It should not have been previously customized or have the customizations disabled.
If you are upgrading Arbortext Publishing Engine, you may have placed 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 upgrade installation only overwrites an existing file having the same name and path. If you placed custom files in other install tree locations, the upgrade could overwrite them. If you prefer a clean installation, you can copy the entire directory and its contents to a backup location. After you complete the upgraded installation, you can migrate your custom files to the upgraded installation custom directory.
Perform the following procedure on your test system to ensure that all customizations have been removed or disabled:
1. Check your environment variables for any that relate to Arbortext Editor.
In general, you should check all environment variables you have set up for your Arbortext Editor environment to make sure they are all relevant and current. For instance, you could have APTCUSTOM set to a path list that has changed due to upgrading to your installation.
2. Record the current settings of any Arbortext Editor environment variables, so that you can reset them appropriately after you have installed the new version.
3. Delete all Arbortext Editor environment variables.
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Once you’ve set the PTC_D_LICENSE_FILE environment variable, don’t delete it. This provides access to your licenses. However, the licenses themselves need to be upgraded. You may need to verify that the upgraded license file or license server location has not changed.
4. Disable any scripts, applications, or files that may be part of the current version's customizations.
You can now install Arbortext Editor on your test system according to the procedures in the installation and licensing chapters.
After you have successfully installed the new version, you will need to perform the post-installation upgrade tasks described in Post-installation upgrade tasks.
Software Upgrade Preparation