As an extra precaution, you may want to disable duplicate messages, to prevent a single recipient from receiving more than one message in your mailing.
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Email Merge Software
Send customized email messages to your customers, building relationships with
them, one email at a time. Send those emails at speeds of over 10,000 messages per
hour! Simple, Fast, and Effective. Free License available.
Fast Sending. Easy Scheduling. Mach5 Mailer has the power to get the message out using a remote SMTP Server, Local SMTP or Mailer Express! Full ESMTP, SSL, and TLS authentication support.
Fast, Multi-Threaded Sending
Mailer can generate up to 30 messages per second and is designed to take advantage of modern Multi-core CPU's.
Mail Scheduling Built-In
Schedule multiple mailings to fire off as often as you like.
Actively Supported, Developed, and Updated
Mach5 Mailer is constantly updated and upgraded with new features, many taken from customer suggestions. We recently released Mailer 4.5 with full Windows Vista support, a free upgrade for all our Mailer 4 customers.