Native POP3 Connector 

Native POP3 Connector offers a standard solution for the problem with receiving mail through the POP3 protocol for Microsoft Exchange Server 2000/2003 and Small Business Server 2000/2003. NPC is a standard solution for MS Exchange Server: Connector.
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IGetMail 

IGetMail works with your Microsoft Exchange email server to download incoming POP3 email from multiple remote servers. It supports individual and group/domain accounts. Uses dial-up networking and operates on a time/frequency schedule you define.
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