MS outlook 2003 is the most widely used email client used among the users nowadays. People prefer it more than other database due to its greater efficiency and usability. It have the capacity to store all essential outlook information related with the programs like emails, calendar events, notes, tasks, personal folders appointments etc are stored in the PST files. So, people mostly prefer to use PST files. An ost file is a component of MS Exchange that resides in our storage device and so it can not be used directly with PST files.