Easy

Assuming you have Outlook, Word and Excel installed . . . .
1) Download a members report in .csv format
2) Open word and select Mailings>Start Mail Merge>Email Messages
3) Then Choose Select Recipients>Use Existing List
4) Browse and select .csv file
5) Write your email template, when you want to add a name select Insert Merge Field>Name
6) Your Template will have the characters <<name>> making your main template "Dear <<name>>”
7) Do the same for your affiliates field select Insert Merge field>Affiliates you will get the text <<affiliates>> appear.
8) You will now have a template with <<name>> for the names and <<affiliates>> for the affiliate codes.
9) Preview the individual email by selecting "Preview results" and selecting the “<” and “>” arrows to flick through the individual mails.
10) Once you are happy select Finish & Merge>Send Email Messages
11) Select the EMAIL field when the box appears, enter a subject and click OK
12) The mails will be sent through the default mail account in outlook
This is how I do it to send personalised emails to affiliates with their own link codes!!
I hope this helps!!