Here's an email etiquette tip some may not know: when you CC: (Carbon Copy) an email to a list of unrelated contacts from your regular account, it is considered to be poor etiquette. This is because all who receive the email will then be able to view each other's private email addresses. Your contacts may or may not wish to have their personal or work email broadcast far and wide, and it's safer to assume that they would rather not.
Next time, use the "BCC:" (Blind Carbon Copy) function to send an email like this. Put your own email address in the TO: field, which sends it to yourself. Put the list of email addresses that you're sending to in the BCC: field to keep everyone's email private.
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