File Extension Database

Open OST File

OST files are data files, usual for the Microsoft Outlook program, in its online version.

In other words, all email services that work online, such as most IMAP account types, Microsoft 365 accounts, Exchange accounts, and Outlook.com accounts use the offline Outlook data file, or OST, to store a synchronized copy of the mailbox information on the local computer.

OST file, takes effect, when the connection to the mail server is interrupted. For example, when you are on a plane without WiFi or if the Internet connection is disconnected, with OST file you can still access all emails, calendar data, Contacts and tasks that have been previously downloaded.

Through the OST file, you can read and compose messages, create appointments, and add contacts.

However, it is necessary to be clear that e-mail messages will not be sent and new messages will not be downloaded until the Internet connection is reestablished.

When the connection is restored, the changes made to the OST file are automatically synchronized and the folders and items on the server and on the computer are identical again.

Software to open and work with an OST file

Frequently associated Windows objects:

  • OSTFile
  • Outlook.File.ost.14

How Can I Open OST File on Windows

How Can I Open OST File on Mac OS

How Can I Open OST File on Android

If you downloaded a OST file on Android device you can open it by following steps below:

How to Open OST File on iPhone or iPad

To open OST File on iOS device follow steps below:

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OST file article translations

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