Email Forwarding System (EFS)
The standard version is available for free. We have been using EFS for a couple of years, and for ~ 50 users. It’s been working beautifully for us.
From the site:
EFS is a FREE POP3 gateway for any SMTP server such as Microsoft Exchange, Lotus Notes or SLMail. It pulls mail from a Pop3 mailbox at your ISP and distributes the messages to users on a local SMTP mail server. EFS requires you to have a registered Internet domain name (to accept and forward mail for) EFS makes an excellent replacement for the somewhat limited Microsoft SBS Pop3 Connector.
EFS collects email from a single pop3 mailbox at your Internet Provider and redirects messages to users mailboxes on your local SMTP mail server, such as Microsoft Exchange, Lotus Domino, SLMail etc (commonly known as “pull-mail” software) The FREE Standard version does NOT have a user or time limitation and will work under most circumstances. You only need to register the advanced or advanced plus versions if you require additional features available.
I’ll second that – we’ve been using EFS for 6 years and its a fantastic product. We’re using the paid version (Advanced Plus) but for well under a hundred bucks its worth every cent. Whats more the developer keeps releasing updates with more functionality which doesn’t cost anymore. A definate 10/10!