What Does Offline Storage Table File (OST File) Mean?
Offline storage table (OST) files are offline files that store Outlook mail data and make it available to users when they are not connected to the Internet. The offline storage tables store mail data using the .ost extension. These files enable users to work with their offline inbox, offline outbox and make changes that are initially saved locally and are reflected in the server by synchronizing once the computer is connected to the Internet. Users can modify, add or delete the contents of these files just as a file located on the server can be modified.
Techopedia Explains Offline Storage Table File (OST File)
Offline storage tables are the files that enable the offline mode of the Microsoft Outlook mail client. They are a type of database file that stores the data copied from the mail exchange server. The data copied include inbox emails, calendar and contacts. All such data and attributes are copied into the local OST files while the system is connected to the network and are stored in local storage under the local mail exchange server. The files are synchronized whenever the system connects to the mail server. Thus offline storage tables act as a cached exchange mode for Outlook.
