Microsoft Office Outlook maintains everything in a data file, also called PST or OST file. It is an offline copy of mailbox data stored on a local PC. In case of ...

Some users have reported that when they open MS Outlook, they receive an error message that Outlook is using an old copy of your Outlook data file (.ost). For some ...

Several Outlook users, on different forums, have reported encountering the error “OST file cannot be opened,” when trying to open the application or sending ...