Yup, that's dBaseIII files ( see thread's title ) and indexes are .NDX.
>I don't think .NDX files are opened automatically. There must be some way to open them via ODBC, but I don't know what that would be. I don't see it in the current message, but weren't you using dBaseIII? I don't remember there being a concept of the .CDX like file being opened automatically until dBaseIV, which I had never gotten to use. Discovered the Fox and never looked back at dBase after III+.
Why do programs stop working correctly as soon as you leave the Fox?