Recovery Toolbox for Outlook can repair the source files of ost format if they become unopenable. However, do you know how to open these files and why they are needed? Since the files of ost format are not available for editing, a great number of users do not know about this extension. So, how to view ost files and is it possible to get back all messages from not accessible Microsoft Exchange Server? You may get Recovery Toolbox for Outlook and enjoy an easy way to open your mailbox in ost format. How to view .ost file? I suppose that you know about the origin of ost files, Recovery Toolbox for Outlook is the only ost file viewer that can successfully view ost files is Microsoft Outlook. Moreover, these files are created by your email client and they should speed up synchronization processes between Microsoft Exchange Server and your email client. If the physical connection with your mail server is lost, the content of mailbox becomes inaccessible and you will not be able to open the source mailbox offline and view .ost files without Recovery Toolbox for Outlook. In the same time, Microsoft Outlook can easily work offline, but your mailbox should be converted to pst format. It is your only chance to view ost files with Recovery Toolbox for Outlook .ost viewer. This ost viewer solution for viewing ost files does not put any modifications to the original mailbox. Unfortunately, other solutions for view ost file can increase the damage of your mailbox and you will not be able to view .ost file like usual.