Microsoft Excel 97 CSV conversion

Have been using the csv file type option to save worksheets into csv (comma delimited) file. Observed that the comma is not showing up from row 17 (1st row = header) onwards. Is there a setting in Excel that controls the maximum nbr of rows. see attached csv file for illustration.

A,B,C
A1,B1,
A2,B2,
A3,B3,
A4,B4,
A5,B5,
A6,B6,
A7,B7,
A8,B8,
A9,B9,
A10,B10,
A11,B11,
A12,B12,
A13,B13,
A14,B14,
A15,B15,
A16,B16
A17,B17