It seems your OST file is corrupted. Hence if you want to open this corrupted ost file and you have availability of Exchange then don’t worry. Since OST is the replica of the Exchange Server mailboxes data it means if OST gets corrupted it can be recreated and assembled downloading all the data again in it. Simply go through the following procedure;
- Locate ost file on the disk and rename it after right clicking on it
- Change extension from .ost to old.ost and hit enter
- Now excess Exchange Server and open Outlook
- It will reconfigure the data file and the new ost file will not be corrupted, one can access it
- Apart from this if you want to open this ost file in PST file format, you can choose Import/ Export Option of Microsoft Outlook.