Symptoms
Assume that you have an account that belongs to a security group, and the account is associated with a linked mailbox. When you log on to the account in Microsoft Outlook and then try to open a shared folder on which the security group has the Reviewer permission, you cannot access the folder, and you receive an error message.
For example, if you try to open a shared Calendar folder by using Outlook, you receive the following error message:You do not have permission to view this calendar.
Cause
This issue occurs because the store worker process (Microsoft.Exchange.Store.Worker.exe) caches the security contexts that are not updated for the token of the account when you access a shared folder. It means that the security contexts do not contain the necessary group membership information. Therefore, the store rejects you to access the shared folder.
Resolution
To resolve this issue, install the following update:
Workaround
To work around this issue, use Outlook Web App, or grant the permission of the shared folder to the account directly.
Status
Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.
More Information
For more information about how to give someone else permissions to access Outlook mailboxes, see How to grant Exchange and Outlook mailbox permissions in Office 365 dedicated.