Reports builder does not launch

I'm trying to get 12C Forms and Reports builder working on a client PC. Other developers in the office are able to use it. I can run Forms builder, but when I try to start Reports Builder, nothing happens except to add to the reports.log "REP-0001: Unable to find the Report Builder message file.  Please verify your installation." I saw a different post saying the directory to the mesg folder must be less than 64 characters. And my directory is less than 64 characters. (C:\Middle_Ware12213\reports\mesg) What are other possible causes are there? And which file specifically is the Report builder