MS Outlookuses two types of files to store all the information of our mail box offile storage table (OST) and personal storage table (PST).OST file is used in case when we work offline and helpful in such cases areas where there is connectivity problem. You keep on doing your work like ceating or deleting mails, and when the connection is restored the OST file gets synchronized with the exchange server to update the changes on both the server and in oST file.
But sometimes due to various reasons regarding connectivity or exchange server the OSt file gets corrupted and becomes inaccessible in MS Outlook. In such a cse you should repair the OST file using the in-built OST Integrity (Scanost.exe) Tool. But the inbox repair tool doesn't work effectively all the time. Now you can use third party OST to PST converter to access all your content in OST file by converting it into PSt file.
Suppose a situation wherein you use Outlook 2007 or any other version. you open the MS Outlook and start synchronize it with the exchange server. But after the synchronization you find that you can not open some or all of the outlook items when you work in offline mode.
The basic reason of this problem is the OST file gets corrupted at the synchronization time. It may get corrupt due to various reasons such as virus infections, human errors, synchronization issues, exchange server issues etc.
In such cases, you should try to scan and repair the OST file using Scanost.exe tool and performing following steps.
Integrity (Scanost.exe) Tool. To do this, you need to perform the following steps:
1) Click Start | Run.
2) Enter C:\Program Files\Common Files\System\Mapi\LocaleID\scanost.exe in the Open box.
3) Press Enter.
4) Click either the Scan all folders option or Choose folder to scan accordingly. Please note that the first option would take several minutes to get completed.
5) Select the Repair errors check box.
6) Click Begin Scan. The OST file will be scanned by the OST Integrity Tool.
7) Restart Outlook. Now you would be able to view those items properly.
However, if the problem is not resolved by performing the above mentioned stepsan dyou are sitll facing the same issue, you should use a third-party OST to PST conversion tool to convert OST file to PST file. Such OST to PST conversion tools are read only that means they are able to convert the OST file into PST file without overwriting the original OST file.