RapidMiner Server stores the licenses inside the /standalone/configuration/licenses/rapidminer-server folder in the RapidMiner Server installation directory. Licenses are simply text files which contain the license string.
Note that the naming convention for them needs to be kept, otherwise RapidMiner Server will not recognize the license file.
To update the actual license key it is recommended to do this from the RapidMiner Server Interface. Following are the steps for updating License keys
Login to Rapidminer account settings and get your license keys.