How do I delete/close my Dropbox account?
1.If you're a Dropbox Pro subscriber, cancel your subscription first.
2.After you're done, click on this link to delete your account.
Deleting your account will delete your account from the website.
Your computers will no longer sync with the website or to other computers or devices. Keep in mind that deleting your account won't remove the files in the Dropbox folder on your hard drive or the hard drives of other members of shared folders you've create