Fixed "Cannot Open Particular Outlook Items When Offline" Error

What OST file consists of mainly depends on the type of mailbox. Whether it is IMAP or Exchange or user is connecting to Outlook.com mailbox with the help of Outlook Hotmail Connector or by using Exchange ActiveSync (EAS).

Exchange account’s OST file is just a cache of data saved on Exchange server. Its main aim is to minimize network traffic, minimize Exchange server’s payload and offers availability, offline. Moreover, it serves as a foundation for so many features in MS outlook that can not be used else wise like instant search, conversation view and the people pane.  Usually, these below-mentioned contents are saved in an Outlook OST data file. These are,

• Public Folder Favorites
• Entire mailbox data like email, calendar, contacts, tasks, etc.
• ‘Overhead’ as found in a PST data file and other hidden items.
• Shared folders of other mailboxes related to Exchange account. 

OST are offline folder files which is the replica of Exchange Server mailbox data and is created when Outlook is used in conjunction of Exchange Server mailbox data and Cached Exchange mode is enabled. Sometimes, it has been seen that OST cannot be accessed and system reported an error as “Cannot open particular Outlook items when offline”.

How to deal with "Cannot Open Particular Outlook Items When Offline" error  

This type of error arises if OST file is corrupted and is not synchronized with the Microsoft Exchange Server. There are several reasons behind corruption of offline OST file as network failures, power failures, improper connectivity, etc. Whatever be the reason but once OST file becomes inaccessible, Outlook fails to recognize it and produces the different error. Since PST files are the proprietary file format used in all the versions of the Microsoft Outlook. Once OST cannot be accessed, converting OST to PST is the best way to recover data from corrupt OST file.

Although, you can also use Inbox Repair Tool to repair corrupt data file of Outlook. It’s a free utility which gets automatically installed in the system when we install MS Office.

Facing trouble for finding location of Inbox Repair Tool?