Using Perl :
Following command will change the orginal file itself so keep a backup copy .
perl -pi -e "s:^V^M::g"
You won't see the Control V on typing but it is needed to generate control
Using sed :
# sed -e `s/^V^M//g` existing_file_name > new_file_name
Using vi :
Open file in vi and enter the following at : prompt in command mode .
BTW There's also a utility dos2unix and unix2dos that you can use to convert characters to and fro DOS and UNIX.