Thank you for reaching out to the Constant Contact Community. It's my pleasure to assist you today.
I'm sorry you are having trouble selecting a list of contacts. In order to select a list when sending an email it must have contacts on the list, if this isn't the case, you might try using a private browsing window or another browser to see if that corrects the issue. If it doesn't please send us an email to social_support(at)constantcontact(dot)com and include your username, the email you are trying to send, the list you are attempting to select, the browser you are using as well as a reference to this post and we will take a look at what may be happening.
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