How to change working days and time in the Outlook calendar
Do the following:
1. On the File tab, click the Options button:
2. In the Outlook Options dialog box, on the Calendar tab, under Work time:
- Modify Work hours
- Select workdays by checking of days
- Choose First day of week and, if it needed, First week of year
See also this tip in French: Comment modifier les jours ouvrables dans le calendrier Outlook.