Load Data Not Working

[Mike Taylor]

Hi,
I just started using workbench and I can't get the load data command to work. Everytime I do it gives me the results

9874 Row(s) affected Records: 4937 Deleted: 4937

Why is deleting them after inserting??? I've never had this problem prior to using workbench.
Here is what I am using

load data local infile 'c:/Users/Mike/Desktop/bounced.csv'
replace into table optout.bounced
fields terminated by ','
enclosed by '"'
lines terminated by '\r\n'
(email);