Welcome to the EMTP help center FAQ > License and Installation An unexpected error "No such feature exists. FLEXnet licensing error -5,21 How to make sure the EMTP version matches or is older than the network license? How to make sure the server hostname in the license file is correct? How to make sure the client license file matches the network license file? How to make sure the Client computer can access to the server hosting the EMTP-RV FlexLM license manager? How to upgrade a network license version? How to activate or update EMTP using a network license file? How to install, set-up and start the EMTP-RV license server manager? What are the system requirements to run EMTP? What are the system requirements for EMTP license server manager?