[1] Since the Office 97 version, most of its functionality was incorporated into the Outlook 97 program.
The first version of Schedule+ was released in 1992 for Windows 3.0 and classic Mac OS.
The initial version of Schedule+ as bundled with version 3.0 of the Microsoft Mail email client had a showstopper bug in that by having the system date roll over to January 1, 2020 (or by setting the year of the date to any year above 2019), the software will halt with an error message saying that it can only accept dates within a 100-year time window between 1920 and 2019.
The version of Schedule+ included with Office 95 onwards (version 7 and up) fixes the aforementioned issue, allowing the software to continue to work with years after 2019.
This Microsoft Windows software-related article is a stub.