For sending email to all contacts, Outlook provides you with no quick feature to select all contacts at once while composing email. Of course you can select all contacts by selecting the first contact and the last one in the contact folder with holding the Shift key on the keyboard simultaneously. But that may be timeconsuming if there are hundreds of contacts existing in this Contacts folder. The best way for sending email message to all contacts in Outlook at once is to create a distribution list with all contacts inside, and then send email to this distribution list. Please browse this article for more detail information.

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