When you purchase webMethods API Gateway, your organization is granted a license to use it with certain features and functionality. The license expires after a time period specified by your purchase agreement.

Before you install API Gateway, you are provided with a license key file that you place in the file system of the machine on which API Gateway will run. This file contains the license key, which is a special code associated with your license. When you install API Gateway, the setup program asks you to provide the name and location of this file. The setup program then copies this file to the SAGInstalldirectory\instances\instance_name\config directory with the name licenseKey.xml. If this file is inadvertently deleted, API Gateway login fails.