If your OST file isn't loading in Outlook, it may be either corrupt or the connection between the OST file and your Outlook profile is broken. Either way, the easiest way to access your mailbox data would be to convert the OST mail items into HTML format so that you may easily open them in a browser. The best option to accomplish this task is to use
FixVare OST to HTML Converter. This handy conversion tool will allow you to convert your OST emails to HTML files without the need for Outlook or an Exchange Server.
Once your OST mail items are converted, you can open the HTML files in any browser(Chrome and Firefox). It offers a free demo version for all users, so they can easily understand it without any trouble.