Free OST Viewer

free ost file viewer


MailsDaddy Free OST Viewer v2.0

The OST file opener free tool is loved by global users.

Use free OST reader application which enables you to open & view content of corrupted, orphaned or offline OST file Independently. The software does not require MS Outlook or Exchange Server for opening OST files on MAC and Windows machines.

  • One click solution to open OST File without Exchange Server connection.
  • Facilitates  users to quickly View OST File contents without its MAPI Profile.
  • Portable OST viewer to read corrupted/orphaned OST file without Outlook.
  • View all items such as: emails, contacts, calendars, tasks and journals etc.
  • Available 100% Free to download for Windows & MAC OS X  both users.
  • Integrated with advance search option to view a required emails only.
  • Support OST files created in MS Outlook 2016, 2013, 2010, 2007 and 2003 etc.

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Installation   Uninstallation   End User License Agreement



Advance Features of Free OST File Viewer Helps to Read OST File Content


Quick Search to Find OST Files

The OST viewer is embedded with the feature to search all files having .ost extension from the selected drive or directly. You can also browse or add OST file manually.

Preview OST File Mail Properties

Once the OST file is loaded, the OST reader software preview all items along with all properties such as: To, CC, BCC, From, Subject, Date and attachments etc.

Read OST File Without Outlook

This is a standalone OST viewer application which does not require Microsoft Outlook to open offline OST files. You can view the content of OST file with Outlook.

Support all kinds of OST files

The Outlook OST viewer supports all types of OST file to scan and view its items even if OST files are corrupted, damaged, password protected or orphaned.



Quickly View Emails in OST File

The OST file opener is a free solution to read messages independently from the OST file. You can View all mail properties by clicking on a particular message.

Read Contacts from OST File

The OST viewer is also capable to fetch all contacts and preview with item counts. You can read contact all properties: name, mobile no, address and birth date etc.

View OST File Calendars

This is the best function of this free OST file viewer tool which enable users to open Outlook calendars and read its subject, start date, end date and location etc.

Forensic Analysis of OST File

You may also use this free OST reader application for forensic analysis of OST file. The tool provides an advance search option to search & view required mails only.



No Need of Exchange Server

This OST viewer program works independently, which does not require Exchange Server or any additional application to view contents of Outlook OST file.

Preserve Folder Hireachay

The software preserves the original folder structure of OST file which helps to read emails from selected folder. You can see all folders in the right panel of OST viewer.

Allows Opening Large OST Files

The tool has been tested on large OST files and work well to read mail from OST file. Thus, you can read OST file of any size without any limitation or restriction.

Available for MAC & Windows

Mailsdaddy provides OST viewers free for Mac and Windows. Download the required application to check how to open OST file in MAC or Windows.

A Breif Introduction About OST File Type & Why OST Viewer Tool is used?

This is the technical information section where you can know about .ost extension and a few scenarios where this OST file viewer comes into demand. This section does not include software related details so if you don't want to read these technical facts so skip this tab.

What is OST File Extension?

OST File extension is an offline storage table file created on client end after establishing a connection between an Exchange server and Outlook using "Cache Exchange Mode". An OST file store email messages, contacts, calendars and other items. The main benefit of .OST file type is that you can access messages in offline mode even internet connection disabled or Exchange server slow down.

You May Need to Read Mails from OST File in the Following Scenarios?

  1. Access Orphaned OST File: The OST file is only accessible when you are connected to the Exchange Server with valid MAPI details. Disconnecting Exchange Server, updating MAPI details, changing file name or path results OST file orphan. To use these OST files you need an independent OST opener application.
  2. Open Corrupted OST Files:  Sometimes OST file gets corrupted due to virus attack, software or hardware related issues which cannot be accessed. This freeware program is the best choice to make them readable.
  3. Read Hotmail OST Files: When you configure your Hotmail account with MS Outlook  it create .ost file extension to save all data. To access these OST files to any other PC or account you need a portable OST viewer software.
  4. Open IMAP OST Files: Microsoft Outlook 2013 and earlier editions create .ost files when you configure your mail account using IMAP server, which are not accessible anywhere. So you can use the free OST reader to view contents of Outlook OST file.

Check How to View OST File on Windows Machine


Watch Online Video of Outlook OST File Viewer Software

MailsDaddy Free OST Viewer Demo Limits & Specifications



By using this free OST file viewer tool you can open and view OST file content along with all Mail properties without any limitations. To enable export functions, you can upgrade this software to pro edition.

Product Specifications:

Application Name: MailsDaddy Free OST Viewer
Developers: MailsDaddy Software
Latest Edition: 2.0
Size 4.25 MB

System Requirements:

Processor & RAM: Minimum 2.4 GHz Processor and 1 GB RAM
Minimum Hard Drive Space: 50 MB
Supported Windows OS: Windows 10, 8.1, 8, 7, Vista, XP and All Older Editions (32-bit & 64-bit)
Supported MAC OS X: Mac OS X 10.11, 10.10, 10.9, 10.8 and all previous editions of MAC OS X
Microsoft Outlook: MS Outlook 2016, 2013, 2010, 2007, 2003 and all previous editions (32-bit & 64-bit)

Frequently Asked Questions for MailsDaddy Free OST Viewer

Yes, The OST file reader is an independent solution which does not require Microsoft Outlook, Exchange Server or any additional program to open and view orphaned OST File.
Yes, you can open and read the password protected OST file without requiring a password.
Yes, You can use this freeware utility on your Mac laptop to view email messages from the OST file. You can download OST viewer for MAC from this website.
Yes, you can open an orphaned, corrupted or offline OST file by using this free OST file viewer application. You just need browse OST file, the software will repair and view all data with item count.
No, there is no file size limitation for opening OST file on MAC and Windows machines. You may add a large OST file to view its content.
Yes, the software supports all earlier and later editions of Windows operating systems including Windows 10, Windows8.1, Windows 7 and Windows Vista etc.
Yes, The tool is available absolutely free for all users and there are no hidden terms and conditions related to Outlook OST viewer tool.
No, free tool does not have an option for exporting items. You need to use the pro edition of the tool to enable all advance features.