When you're writing a business letter or sending an email message, it's important to close your letter in a professional manner. The ideal ending for a business letter conveys your thanks and respect, without eccentricity or an overly familiar tone. Although it may seem old_fashioned, most business professionals expect written correspondence – whether via a letter or an email – to be written and formatted in a conservative manner.
Sometimes a person's gender is unclear from a name _ names like "Corey" or "Blake," are both common women's and men's names. If that is the case, do some investigating to determine gender from searching on LinkedIn or a company website. But if it remains ambiguous, simply write out the person's full name, dropping the title. For example, "Dear Corey Meyer."