
This includes add-ins that are used to set up conference rooms.

But you can maintain the connection to only one folder at a time. Remove the ActiveSync relationship from Outlook Web App. You can use IMAP IDLE to maintain the connection to the IMAP server and apply changes that you make to the read, unread, or flagged status of messages on the server. Remove the ActiveSync relationship on the mobile device. Depending on how you connect to Exchange Online, the specific steps will vary. To troubleshoot this issue, re-create the ActiveSync relationship on the mobile device. Typically, the calendar on the mobile device is missing events that appear in Microsoft Outlook or in Outlook Web App in Exchange Online.

Calendar items that are created in the Exchange Online mailbox are missing from the mobile device.Calendar items that are created on the mobile device are missing from the Exchange Online mailbox.On Windows, you can just go to Settings > Date and Time to check this. For example, you experience one or both of the following symptoms: If even one device has an outdated date/time, then it can lead to the iCloud calendar not syncing problem. Click the box next to Sync calendars with, then select Outlook. It's next to a circled 'i' on the left side of the window. Also, if your Outlook account has not been connected to your iPhone properly, then the Outlook calendar would not be synced correctly. You should see all the information for your iPhone, including a new menu on the left.

When you use Microsoft Exchange ActiveSync to connect a mobile device to Exchange Online in Microsoft 365, the calendar on the mobile device and the calendar in the Exchange Online mailbox are out of sync. Click the name of your iPhone in the left sidebar of iTunes.
