Kernel OST Viewer

View healthy & corrupt OST emails and attachments

*Download absolutely free software and view healthy/corrupt OST file data

  • Opens OST file(s) without Exchange account/MS Outlook
  • Displays all OST items including emails, attachments, Deleted Items, Calendar, Contacts, etc.
  • Works with healthy & corrupted OST files
  • Allows to Copy & Print the OST email list in HTML Format
  • Find Specific OST email items
  • Creates a comprehensive file analysis report to analyze OST data
  • User-friendly Graphical User Interface
  • Compatible with all Exchange and Outlook versions
  • Opens OST email attachments
OST Viewer Tool – What’s it for?
Opening OST mailbox items without Exchange profile/connection
Viewing orphan, corrupt and healthy OST files without Outlook
Viewing email data by Date, From, To, etc.
Viewing attachments of OST file emails
Saving OST email list in HTML format
Viewing analytical reports on OST file content

By reading the above points about the tool, 2 questions may arise in your mind

What is an OST file?

OST file stands for Offline Storage Table which is an offline copy of the Exchange mailbox. You can make changes in OST file content in offline mode. The changes made in OST file will get automatically updated by synchronization when connected with Exchange Server.

Where is the OST file located?

OST file can be found without opening Outlook/Exchange by 2 ways

1. Searching at default location You will find the OST file at this default location - C:\Users\user\AppData\Local\Microsoft\Outlook Or C:\Documents and Settings\\Local Settings\Application Data\Microsoft\Outlook
2. With Search option in OST Viewer tool In OST Viewer tool, Search option automatically extracts all the stored OST files from the specified drive at one go.
To perform this, enter the drive location and click Search in Source File Selection dialogue box. All the OST files are extracted at once, thus making the task of locating OST file convenient for users.
Salient Features
Access OST Files Without Exchange Server

Access OST Files Without Exchange Server

OST Viewer tool allows access to Exchange Offline folders file (OST) without establishing a connection with MS Exchange Server. The tool scans OST file and displays its entire content including emails, calendar items, notes, contacts, etc.

Find and Open Emails

Find and Open Emails

With OST Viewer tool, you have the privilege to access particular email items with ‘Find’ option. In the selected mailbox folders, you filter the emails by From, To, Subject, Date Range, Attachments, etc. Thus you can locate and preview specific emails.

Saves Email List in HTML

Saves Email List in HTML

The OST Viewer tool allows you to save the list of OST emails in HTML format. You can copy or print this list. The tool also provides access to email attachments in a single click.

Opens All Kinds of OST Files

Opens All Kinds of OST Files

OST Reader tool is capable of opening healthy as well as corrupt OST files. The software is capable of opening OST files without connecting to an Exchange profile.

Search OST Files Within Disk Drives

Search OST Files

The tool makes the task of finding OST file easier with the Search option. This option locates the OST file within the specified location. You need to enter the drive in which you know your OST file is located. The tool will automatically fetch the OST file, and you can open it by clicking on it.

Open Multiple OST Files

Open Multiple OST Files

You can open as many OST files as required. There is no restriction in the number of OST files to view. You can add multiple OST files with the + button in the Source File Selection dialogue box. This feature saves the users’ time from adding individual OST files one-by-one.

Generates File Analysis Report

Generates File Analysis Report

Free OST Viewer tool creates reports having details of all item types such as emails, contacts, email flow density as per sender or data, notes, etc. It helps you analyze the OST file data.

High Software Compatibility

High Software Compatibility

Kernel OST Viewer Free tool extends support for all versions of MS Exchange Server (2019, 2016, 2013, 2010, 2007, 2003, 2000, 5.5, and 5.0), MS Outlook (2016, 2013, 2010, 2007, 2003, 2002, 2000, 98, and 97).

Kernel OST Viewer is an easy to use software that can view all your healthy or corrupted OST files in few simple steps. Let’s check them out.
  • Run the software and click on the Browse button to select a single or multiple OST file(s) and click on Next to proceed.
  • The system will show you the Process Information; there you need to click on the Finish button.
  • In the next step, you need to click on the files you want to view. Select them one by one to view the content.
  • Note: You can also generate an analysis report. For this, you need to select the type of report you want to generate from the right corner of the screen.

You can configure an Office 365 account in Outlook using IMAP configuration. Then as the rest data is saved as a copy of mailboxes in OST file, the configured Office 365 data is also copied in local OST file.
OST file, as we know is an offline copy of the mailbox available on the Exchange. To access OST file with latest information, its synchronization with Exchange is needed. When the mailbox is unavailable on Exchange Server permanently, then the OST file is termed as orphaned OST file.
Yes. You can view the attachments in the OST emails. Here are the steps:
  • Step1: Select the folder from left pane
  • Step2: From the right pane, select the email of the attachment you want to open
  • Step3: In the email preview double click on the attachment.
You can use Search option in OST Viewer tool to find your OST file easily by providing the drive location.
Using the File Analysis Reports feature, you can have the overall information about the content of OST file. Let us have a look at the reports available.
  • Total item types: Generates a graph between Total item types and item count.
  • Mail flow density by date: Generates a graph between Item count and date.
  • Mail flow density by senders: Generates graph between Item count and senders.
  • Interaction between users: Generates graph between Item count against Sender & Receiver pair.
Steps to Open and View OST file

Kernel for OST viewer is a software made specifically to have a Preview of the complete data residing in OST files. With its simple interface, you can view OST data in 3 easy steps.

Add single or multiple OST files
Use Search option to fetch all OST files
Select any file item from the OST mailbox
Client Testimonial
Software Specifications
System Requirement

Supported Versions Windows 10/ 8.1/ 8/ 7/ Vista/ XP/ 2000/ 98/ NT/ 95

ProcessorPentium Class
Memory + Hard Disk64 MB RAM (128 MB Recommended)
50 MB of disk space
Software Delivery & Version

User Reviews
Kernel OST Viewer Kernel OST Viewer
(4.9 / 5) 452 Reviews
A fantastic tool to work with and a great interfaceeasy-to-use navigation.
Full StarFull StarFull StarFull StarFull Star
I have used many tools of Kernel and I can say that all the tools are easy-to-use efficient cost-effective and result-oriented.
Full StarFull StarFull StarFull StarFull Star
Kernel OST Viewer is a free utility which makes it even more reliable and trust worthy than other similar tools available online. With great tool comes great support, they provide a quick revert on your queries. A must recommended tool from my side.
Full StarFull StarFull StarFull StarFull Star
Granville Barrett
1 > Last
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