Runtime error messages that appear in ESL are, by default, in English. They are maintained in an external file, ESLERR.EMO. This file is in a binary format, which is maintained using the ESL Message Manager tool (EslMsgMgr). By translating the message text that appears in the source message list file, then processing the file using EslMsgMgr, an ESL developer can ensure the messages reported by both the ESL runtime and compiler are in the required language.