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 ...

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

If you open MS Outlook and see an error message, Outlook is using an old copy of your Outlook data file (.ost), then use ...