You may need Outlook OST file to PST file conversion for one or several reasons. Nonetheless, when this is the need, the very first thing that you would have to do is perform Microsoft OST to PST converter free download of Stellar Converter for OST. Once done so, i.e. The software is downloaded you can easily install, configure/register and then run the software to convert Outlook OST file to PST file. You can even restore deleted or inaccessible mailboxes from corrupt or damaged Outlook’s offline (OST) data file with the use of this by Stellar Data Recovery. Need of Microsoft OST to PST converter The need of Microsoft OST to PST converter arises if you wish to convert Outlook offline (OST) data file to Personal Folders (PST) file. The various reasons for this conversion are as follows: • Move or migrate data of Exchange mailbox database to Outlook • Exchange Server becomes dismounted or non-functional due to crash • Move mailbox data from one location to the other • Damaged OST files make Exchange mailbox data inaccessible • Lack of effective and efficient OST file repair utility • Data recovery after accidental deletion or corruption of OST files Ways of converting Microsoft Outlook OST file to PST file I.