Article ID: 2599434 - View products that this article applies to.
Consider the following scenario:
This issue occurs because the Public Folder Calendar folder in the Favorite list cannot be recognized correctly when the OWA Calendar module is loaded. Therefore, the folder is incorrectly added to the InvalidNodeList list, and then the folder is removed.
To resolve this issue, install the following update rollup:
(http://support.microsoft.com/kb/2645995/ )Description of Update Rollup 1 for Exchange Server 2010 Service Pack 2
For more information, click the following article number to view the article in the Microsoft Knowledge Base:
(http://support.microsoft.com/kb/2417084/ )A public folder disappears from the Public Folder Favorites list of an Exchange Server 2010 mailbox