I have set up a SAP server for testing purpose, it is fine when I login the system by using the language English. However when try to login the system by enter the 'ZF' in the field of 'Language', the system told me that "Select one of the installed languages". I have no idea after I find many documents from SAP. Therefore please help to tell me that how to install a language -- I want user can choose the language Chinese or English during logon. The system is ERP 6.0. Thanks in advance!