XADM: Outlook Client Offline Folder File Synchronization Is Not Successful If There Is a Large Number of Items in the the Exchange Public Folder

You cannot successfully use Microsoft Outlook to synchronize the contents of an offline folders file (.ost) with a Microsoft Exchange public folder. The public folder may have a large number of items that change frequently, although the number of items is less than the documented limit of 65,536 items per folder.

This problem may occur if the public folder is busy, such as if the number of items that are removed by aging limits and the number of new items that are created in the public folder on a daily basis are generally large.

For example:

• 50,000 items are present in a public folder.
• During the next Information Store maintenance cycle, 15,000 items in the public folder are removed due to Public Folder item aging limits setting. This removal brings the total number of items to 35,000.
• The next day 20,000 items are added to the public folder, which brings the total number of items to 55,000.

This problem may also occur if you have not used the Microsoft Outlook client to synchronize the contents of the .ost file for an extended period of time.

To work around this problem, for extremely busy public folders, consider redistributing the contents of public folders across several different public folders.

Microsoft has confirmed that this is a problem in the Microsoft products that are listed at the beginning of this article.