How can I send a same e-mail to a list of contacts with an attachment and to another list of contacts without the attachment?

Follow the steps below to do this:

1. Create the e-mail to be sent (Do not attach the attachment file).
2. Use EmailMerge to send to people who do not need the attachment.
3. Once Wizard is completed the original e-mail you created will be shown again.
4. Attach the attachment file to this e-mail.
5. Use EmailMerge to send to people who do need the attachment.