A common question Exchange users want to know is how to access shared calendars and contacts on a smartphone. While the usual answer is “you can’t”, it is possible to open a link to the shared calendar in OWA, which allows it to sync as a calendar within your mailbox and sync to devices (and to Outlook).
The negatives? The ics file is very slow to update. If you have the shared calendar opened in Outlook, you'll have two copies: the subscribed ics file opened in your mailbox and the calendar that is opened as a shared calendar through Exchange. You'll want to use the calendar shared via Exchange in Outlook because it updates much faster than the subscribed calendar.
Is the published calendar read-only or editable? In Outlook they are read-only. In OWA and on the devices they appear to be editable and changes sync back to the server, then disappear. At this point in time, I would not create or edit appointments on the published calendars.
This works with any published calendar, including Gmail and Outlook.com. The only requirement is that you need an .ics file. It will work with Shared Exchange calendars, provided sharing policies allow it. The owner needs to publish the calendar and send you a link.
Publish the Calendar
The person who is sharing the calendar needs to publish the calendar to the Internet and send you a link to the ics file. This can be done from Outlook or Outlook on the web.
- Right click on the calendar you wish to share
- In Outlook the Share, Publish calendar command
- Change the Publishing details as needed. (This screen comes up when you publish the calendar from Outlook.)
- Send the private .ics link to the people who need to open the calendar.
- In Outlook on the web, click on Share Calendar
- A sharing message opens. Add the address and set publishing details then send. The message will have the .ics link when sent to addresses outside of the organization.
Office 365 shared calendar notifications sent to addresses on Office 365 contain an XML file, not a link. The mailbox owner can get an .ics link from the Calendar Permissions property page. Right click on the calendar, choose Permissions the right click on the Subscribe to Calendar link.
To share a calendar in a shared mailbox you have access to, open the shared mailbox in OWA using the Open another mailbox command (click on your photo or the person icon in the upper right to expand the menu), then follow the steps above to share the calendar.
Group calendars and Public Folder Calendars cannot be published or shared.
Open the Shared Calendar File
Although you can open the .ics file as a published calendar on Apple devices and in Outlook desktop, it's a read-only calendar. If you open it in OWA it's stored in your mailbox and is available everywhere you open your mailbox. If you use the Outlook app, you'll need to add it to OWA as you can't subscribe to calendars separately.
To add the calendar to OWA:
- Log into OWA
- Right click on a Calendar group
- Choose Open calendar
- Paste the .ics link into the From Internet field
The calendar opens in OWA. It will sync down to Outlook within a few minutes. The calendar can be renamed.
Wait a few minutes and open the Calendar app on your smartphone. The new calendar should be in the Calendar list on the native Apple and Android apps and in the Outlook app on both Android and iOS.
Warning: it can take a very long time for new appointments to sync to other devices. Changes made in Outlook or OWA also took hours to sync to the devices. For this reason, it’s not a good solution for a busy calendar that is updated often. Using a licensed mailbox and opening it as an Exchange mailbox would be better.