C3011   Can't open standard rule file

     Explanation:  The compiler cannot open the standard header file
     (i.e., either Std.ch or the file specified with the /U compiler option).

     Action:  The compiler searches for the standard header file as it
     does for any other header file, looking in the current directory and
     then in the INCLUDE path.  Update the INCLUDE environment variable with
     the proper location or add a new location to the front of the current
     include list with the /I option.