Microsoft > Exchange
Microsoft Exchange has proven to be a valuable product for businesses large and small since became available to the public in 1996. Exchange serves as a calendaring and mail server and has its roots as the mail client for Microsoft corporate headquarters. In the early days, Exchange exclusively used the proprietary protocol MAPI. After Exchange became available for use outside the walls of Microsoft, support for POP3, IMAP and SMTP was added.
Microsoft Exchange Server 2019 Standard Device CAL - CSP MFR # CSP-DG7GMGF0F4MB-0005
Microsoft Exchange Server 2019 Enterprise - CSP MFR # CSP-DG7GMGF0F4MF-0003
Microsoft Exchange Server 2007 Standard Academic - 5 Cals MFR # 8.82E+11
Microsoft Exchange Server 2003 Enterprise 25 CAL MFR # 395-02831