How To: Send As A Different Address Outlook Desktop
  1. Click new email to open the new mail window
  1. If you don't see the "From" field
  2. Click Options
  1. Click "From"
  2. Click From Field
  1. If the address is not shown
  2. Click "Other Email Address..."
  1. Type the email address
  2. Or click "From" to select from the address book