This method will guide you to configure view settings and conditional formatting to add the specified color category for today’s appointments automatically. Please do as follows:

1. In the Calendar view, select the calendar that you will automatically color today’s appointments, and click View > View Settings.

2. In the opening Advanced View Settings: Calendar dialog box, please click the Conditional Formatting button. See screenshot:

3. Now the Conditional Formatting dialog box comes out, please configure as follows:
(1) Click the Add button to add a new color rule;
(2) Type a name for the new color rule in the Name box;
(3) Select a color from the Color drop down list;
(4) Click the Condition button. See screenshot:

4. In the popping out Filter dialog box, please (1) go to the Appointments and Meetings tab, (2) select starts from the Time drop down list, and then (3) select Today from the drop down list right to the Time box. See screenshot:

5. Click the OK buttons successively to close all dialog boxes.

Now all appointments starting today are highlighted with the specified color automatically in the selected calendar. See screenshot:

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