If you want to open Open Ost File you need to have a RTB (RECOVERY TOOLBOX FOR OUTLOOK)
OST files are a product of Microsoft Outlook, and contain your offline e-mail data.
Working offline means you have access to your data in situations where a connection to your e-mail server cannot be established. To make this possible, your data must be saved locally on your workstation.
.OST files are a format used by Microsoft Outlook to save your offline data on your workstation. The next time you have a connection and are Outlook can communicate with the e-mail server, your data from the .OST file can be synchronized with what’s on the server.
Recovery ToolBox for Outlook (download) is designed to recover data from Microsoft Outlook pst files.
The Microsoft Outlook mail client is part of the Microsoft Office software package and is one of the most popular mail clients in the world.
The program can be also used to recover information from Microsoft Exchange ost files and/or convert them into Microsoft Outlook pst files.
