Depends entirely on the application that is "expecting" the .asc file.
But you may get by just renaming. A ".csv" file just "generally" means
its a text file with the "fields" separated by commas.

Quco wrote:

What is the CORRECT procedure to convert a CSV file (a comma delimited file)
that I created using Excel 2007, to an ASCII file? I think there is more than
just changing the extencion from *.csv to *.asc