File extension OST
| File type | Microsoft Outlook Inbox Off-line Folder Format |
| Developer | Microsoft |
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What is a OST file?
File with an .OST extension contains locally stored data downloaded from the Exchange server with Microsoft Outlook. It may be email messages, contacts or attachments also of large volume, unlike the similar PST files (Personal Folder), which by default support smaller volume files. The maximum volume of both files can be changed with proper entries in the register.
OST files are used by MS Outlook programs from the 2005 version, if the Offline catalogues option is chosen, which enable access to the data without necessity to connect to the Internet. In such case, they are stored on a local drive.
Program(s) that can open the .OST file
How to open OST files
If you cannot open the OST file on your computer - there may be several reasons. The first and most important reason (the most common) is the lack of a suitable software that supports OST among those that are installed on your device.
A very simple way to solve this problem is to find and download the appropriate application. The first part of the task has already been done – the software supporting the OST file can be found in the table. Now just download and install the appropriate application.
Possible problems with the OST format files
The inability to open and operate the OST file does not necessarily mean that you do not have an appropriate software installed on your computer. There may be other problems that also block our ability to operate the Microsoft Outlook Inbox Off-line Folder Format file. Below is a list of possible problems.
- Corruption of a OST file which is being opened
- Incorrect links to the OST file in registry entries.
- Accidental deletion of the description of the OST from the Windows registry
- Incomplete installation of an application that supports the OST format
- The OST file which is being opened is infected with an undesirable malware.
- The computer does not have enough hardware resources to cope with the opening of the OST file.
- Drivers of equipment used by the computer to open a OST file are out of date.
If you are sure that all of these reasons do not exist in your case (or have already been eliminated), the OST file should operate with your programs without any problem. If the problem with the OST file has not been solved, it may be due to the fact that in this case there is also another rare problem with the OST file. In this case, the only you can do is to ask for assistance of a professional staff.
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This extension
can be converted to:
How to associate the file with an installed software?
If you want to associate a file with a new program (e.g. my-file.OST) you have two ways to do it. The first and the easiest one is to right-click on the selected OST file. From the drop-down menu select "Choose default program", then click "Browse" and find the desired program. The whole operation must be confirmed by clicking OK. The second and more difficult to do is associate the OST file extension to the corresponding software in the Windows Registry.
Is there one way to open unknown files?
Many files contain only simple text data. It is possible that while opening unknown files (e.g. OST) with a simple text editor like Windows Notepad will allow us to see some of the data encoded in the file. This method allows you to preview the contents of many files, but probably not in such a structure as a program dedicated to support them.