If you are going to share your calendar via email, but prevent the recipients from viewing the appointment details, you can do as follows in Outlook.

1. In the Calendar view, right click the calendar you will share, and select Share > Share Calendar from the context menu. See screenshot:

2. In the Sharing invitation window, please add recipients you will share the calendar with, specify Availability only or Limited details from the Details drop down list, and click the Send button.

3. In the popping out Microsoft Outlook dialog box, please click the Yes button to go ahead.

When recipients receive this email and open the calendar in their Outlook, they will only view the appointments without details.

Note: This method can only work with Exchange account in Outlook.

If you have granted other Exchange users permissions to view your Outlook calendar, you can hide all appointment details in the shared calendar by the Calendar permission feature.

1. In the Calendar view, right click the specified calendar you have shared with other Exchange users, and select Properties from the context menu. See screenshot:

2. In the Calendar Properties dialog box, please go to the Permissions tab, and then: (1) Select the specified Exchange user whom you will prevent from viewing all appointment details in your shared calendar;
(2) Select Reviewer from the Permission Level drop down list;
(3) In the Read section, please check the Free/Busy time, subject, location option. See screenshot：

3. Now the permission lever of the specified Exchange user is changed to Custom. Please click the OK button to save the change.

From now on, the specified Exchange user won’t view the appointment details in the shared calendar, such as category color, etc.

Allow others to edit your shared calendar in Outlook