1 .Open the Calendar of the Sharepoint site
2. In the Calendar Tools tab, select Calendar and click on Connect to Outlook
3. When prompted if you want to allow the website to run a program on your computer click on Allow
4. Outlook will then ask you if you want to connect the Calendar, click on YES
5. The Sharepoint calendar will then be visible in the Outlook Calendar if it is selected on the left side under Other Calendars
6. The default view for an additional calendar in Outlook is side by side, if you want the Sharepoint calendar to overlay the Outlook calendar, go in the Outlook Calendar to the View tab and select the Overlay option