Thank you for reaching out to the Constant Contact Community. It's my pleasure to assist you today.
That's a great question. During your trial period, you are able to send to up to 100 contacts. If the list you uploaded has more than 100 contacts on it, it will be greyed out. You can create a new list and add just 100 contacts to that list and you will then be able to send the email. Here is more information about your Constant Contact trial. Please feel free to reach out should you need anything else.
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