Installing Arbortext Publishing Engine > Arbortext Publishing Engine Licensing > PTC_D_LICENSE_FILE Environment Variable
  
PTC_D_LICENSE_FILE Environment Variable
Arbortext Publishing Engine looks for the path to a FlexNet node-locked license file in the PTC_D_LICENSE_FILE environment variable automatically when it starts. If PTC_D_LICENSE_FILE does not exist or has an incorrect value, you will need to specify it.
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By default, Arbortext Publishing Engine is installed under the Windows SYSTEM account. If you start Arbortext Publishing Engine and PTC_D_LICENSE_FILE does not exist or has an incorrect value, its Arbortext PE sub-processes will report a license error.
If you try to start Arbortext Publishing Engine Interactive without a valid PTC_D_LICENSE_FILE, you will see a Licensing Error dialog box prompting you for license information. Because this dialog box will set the variable as a User variable, Arbortext PE sub-processes will still be unable to find the license. Be sure PTC_D_LICENSE_FILE is set as a System variable in the server’s System Properties.
Refer to Troubleshooting Arbortext Publishing Engine Licensing for information on how to obtain a licensing report from the Arbortext PE server.
It’s possible that a license administrator has deployed the licensing information to the Arbortext PE server by setting the PTC_D_LICENSE_FILE environment variable. You may never be prompted for the information unless you encounter a license problem.