Task Plus Professional 

Task Plus Professional is a powerful multi-user scheduling calendar handling up to 100 simultaneous users on a local area network. A color coded 4-month calendar is on screen at all times. Tasks include priority, private, rtf notes, who fields.
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Task Plus 

Task Plus is a very graphical freeware task and 4-calendar scheduler designed for simplicity and speed. Unlimited number of personal tasks on the calendar with holidays and repeating events such as birthdays. 4 month calendar is color coded.
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