Used SuperMailer for Windows?
Developer’s Description
By Mirko Boeer
SuperMailer can send personalized serial mails (for newsletters, marketing campaigns) as plain text or HTML (WYSIWYG Editor and inplace editor) with (personalized) attachments using up to 10 threads simultaneous. It can manage the recipients of the message, the e-mail content, and the attachments as projects so you can reuse it. It uses a SMTP server, Office 365, Microsoft Outlook or a MAPI capable client to send e-mails.
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