OST File Extension

OST file icon
Outlook Offline Folder Format
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What is OST file?

OST file format is used by Microsoft Outlook mailing software. The file can contain data such as email messages, tasks, calendar data or contacts. OST files are used as offline mailbox files if applications is not connected to Micr o soft Exchange server. OST format is also known as Offline Folder File (OFF).

OST files applications

OST is a offline folder file that enables user to perform certain tasks without the need of active internet connection – all changes made by the user will be synchr onized with Microsoft Exchange server upon connection. OST file enables creation of contacts, tasks, email messages and other elements while offline. This features is especially useful in places with limited internet access.

Cretion and location of OST files

OST files is created immediately after choosing ‘Use offline folders’ option available in Microsoft Outlook utility. Upon generation, the file is stores on local hard disk drive, not on the mail server. OST file folder path:

Users[user name]AppDataLocalMicrosoftOutlook.

Similarities to PST format

OST format shares many similarites with PST, however the latter stores data on network cli e nt or server other than Exchange server. OST format supports larger file sizes than PST.

Programs that support OST file

Conversion of a OST file

When you install one of the applications from the list of programs that you found here, you should be able to open or edit the file with the OST extension without any issue. However, if you still have problems with this, you may use the option of OST file conversion to a different format.

File Conversions from OST extension to a different format
File conversions from other format to OST file

We hope we helped you solve the problem with the OST file. If you do not know where you can download the application from our list, click on the link (which is the name of the program) - you will find more information there on the location where to download the secure setup version of the required application.

What else may cause problems?

There can be more reasons which determine that you are not able to open the OST file (apart from the lack of the proper application installed).

First - the OST file may be incorrectly associated with the application installed to support it. In this case, you need to change this association by yourself. To do this, right-click on the OST file that you want to edit, click "Open with" and then select the program from the list that you have installed. After this operation, the problems with opening the OST file should be solved.

Second - the file you want to open can simply be damaged. Then, the best solution is to find a new version of given file, or download it again from the same source as before (maybe for some reason in the previous session the download of the OST file has not been completed and it cannot be opened properly).

Do you want to help?

If you have additional information about the OST file, we will be grateful if you share it with our users. To do this, use the form here and send us your information on OST file.

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