OST to PST Converter

Microsoft Outlook is a popular email client used by millions. It stores mailbox data in two file formats — OST and PST. Sometimes, users need to convert OST files into PST format. This may happen during system crashes, Outlook migration, or profile deletion.

In this guide, you’ll learn how to convert OST to PST manually for free. We'll also show how ATS OST Converter can help if manual methods don’t work.

What Is an OST File?

An OST file is created when Outlook connects with Exchange Server, Office 365, or an IMAP account. It allows you to work offline. When your internet connection returns, all updates sync automatically.

Key Points:

Tied to a specific Outlook profile.

Becomes useless if the account is deleted or the server is down.

Useful for offline work and automatic syncing.

What Is a PST File?

A PST file stores your Outlook data locally. You can back it up or move it to another system.

Key Points:

Great for storing, archiving, or moving data.

Can be used on different systems.

Easy to import into Outlook.

Why Convert OST to PST?

There are many reasons to convert OST to PST:

To back up important emails.

When the Exchange server is not available.

To move data to a new computer.

To access data from an old Outlook profile.

For legal or compliance needs.

Manual Methods to Convert OST to PST for Free

You can use Microsoft Outlook’s built-in features to do this. These methods are free but only work if you still have access to the Outlook profile.

⚠️ If your OST file is orphaned or corrupted, manual methods won’t help. Use professional software instead.

Method 1: Use Import/Export Feature in Outlook

This is the easiest and safest manual method.

Steps:

Open Outlook.

Go to File > Open & Export > Import/Export.

Choose Export to a file and click Next.

Select Outlook Data File (.pst) and click Next.

Pick the folders to export. Check Include subfolders.

Choose where to save the PST file.

Click Finish.

Method 2: Use the Archive Feature

This helps move older emails into a PST file.

Steps:

Open Outlook.

Go to File > Options > Advanced.

Click AutoArchive Settings.

Choose how often to archive and the file location.

Click OK.

Outlook will now move older items to a PST file based on your settings.

Limitations of Manual Methods

These manual options are useful, but they have limits:

You must access the original Outlook account.

They don’t work with corrupted or orphaned OST files.

Large files take a long time to export.

There's no option to filter or split data.

Errors can happen if the process is interrupted.

Better Option: Use ATS OST to PST Converter

If you can't use manual methods, try ATS OST Converter. It’s a powerful tool that helps you convert OST files easily—even if they are damaged or orphaned.

Why Use ATS Software?

Works without Outlook or Exchange Server.

Converts OST to PST, Office 365, Gmail, MBOX, and more.

Recovers corrupted OST files.

Keeps your folder structure and email formatting.

Lets you preview emails before saving.

Supports bulk export.

It’s a great option for users who want to save time and avoid data loss.

🔗 Download the free trial from the official website Ayush Tech Software.

Tips Before You Start

Whether you use manual methods or software, follow these tips:

Always back up your OST file.

Make sure Outlook is working correctly.

Free up space on your drive for the new PST file.

Don’t interrupt the process once it starts.

Conclusion

It’s possible to convert OST to PST manually for free using Microsoft Outlook. You can use the export, archive, or drag-and-drop methods. These are good choices if you still have access to your Outlook profile.

But if the file is corrupted or you’ve lost the original profile, manual methods won’t work. In that case, tools like ATS OST to PST Converter offer a smart and secure way to export your data.

Choose the method that suits your situation. Just make sure your data stays safe.

Frequently Asked Questions (FAQs)

Q1: Can I convert an OST file to PST without Outlook? Manual methods require Outlook. If you don’t have Outlook access, use a tool like ATS OST Converter.

Q2: Is the manual method good for bulk email migration? Not ideal. Manual export is limited and time-consuming for bulk data. Use professional software for batch export.

Q3: What if my OST file is corrupted? Manual methods won’t help. Use ATS OST Converter to recover and export data safely.

In an increasingly connected digital ecosystem, managing email across platforms and formats is no longer a technical luxury—it’s a necessity. For users transitioning from email clients like Thunderbird, Apple Mail, or Eudora to Microsoft Outlook, converting MBOX files to PST format is often a critical step. Choosing the right MBOX file converter software ensures a smooth transition with no loss of data or structure.

This guide explores the technical background, practical benefits, and key features to expect from professional MBOX to PST converter tools—helping you make an informed, secure, and efficient migration.

Understanding MBOX and PST Formats

Before beginning the conversion process, it’s important to understand what each file format represents:

MBOX (Mailbox Format): A standardized format used by various open-source email clients such as Mozilla Thunderbird, Apple Mail, Eudora, and Entourage. It stores emails as plain text in a single file, appending messages sequentially.

PST (Personal Storage Table): Microsoft Outlook’s proprietary format that stores emails, contacts, calendars, notes, tasks, and attachments in a structured database optimized for Outlook and Exchange environments.

Why Convert MBOX to PST?

Converting from MBOX to PST is essential in multiple scenarios:

1. Transitioning Email Clients

Switching from MBOX-supported clients (e.g., Thunderbird or Apple Mail) to Outlook requires conversion to maintain access to previous mail data.

2. Enterprise Integration

Outlook is the standard in enterprise environments due to its integration with Microsoft Exchange Server and Microsoft 365. PST files are fully supported within these systems.

3. Enhanced Data Management

Outlook offers superior features for managing tasks, scheduling, and organizing emails compared to most MBOX-based clients.

4. Regulatory Compliance and Archiving

PST format supports robust encryption, archiving, and legal compliance features, crucial for business and legal teams.

Drawbacks of Manual MBOX to PST Methods

Manual workarounds like exporting emails to EML format and importing them into Outlook can be unreliable and time-consuming. They often result in:

Loss of formatting or metadata

Broken attachments

Incomplete folder structures

Long processing times

For reliable, scalable, and professional outcomes, a dedicated MBOX file converter software is strongly recommended.

Key Features of Professional ATS MBOX to PST Converter Software

The ATS MBOX to PST Converter Software is engineered to simplify and secure the email migration process from MBOX-supported email clients to Microsoft Outlook. Packed with intelligent features, it ensures high data integrity, speed, and flexibility throughout the conversion journey.

Batch MBOX File Conversion: Convert multiple MBOX files into PST format in a single operation. Ideal for IT admins or users managing large email archives.

Maintains Original Folder Structure: Preserves the original hierarchy of folders and subfolders during migration, ensuring seamless email organization post-conversion.

Complete Metadata & Email Integrity: Complete Metadata & Email Integrity

Preview Before Conversion: Built-in preview panel lets users verify and read email messages before exporting them to PST, ensuring accuracy and transparency.

Selective Export Capability: Choose specific folders, emails, or date ranges to convert—saving time and avoiding unnecessary data transfer.

Supports Multiple MBOX Sources: Compatible with MBOX files generated by Thunderbird, Apple Mail, Eudora, Entourage, PocoMail, and more.

Who Should Use MBOX to PST Converter Software?

This software is ideal for:

Home users switching from open-source email clients to Outlook.

System administrators performing enterprise-scale mailbox migration.

Forensic analysts converting MBOX evidence for legal or investigative review in Outlook.

Backup teams needing to archive MBOX files in a compliant PST format for long-term storage.

Conclusion

Migrating from MBOX to PST doesn’t have to be risky, complex, or time-consuming. By selecting a reliable MBOX file converter software, you can ensure complete data integrity, maintain formatting, and facilitate a seamless move into the Microsoft Outlook environment.

In the digital age, where email communication reigns supreme, maintaining an efficient and organized mailbox is imperative. Microsoft Outlook, a widely used email client, offers a handy feature known as "Archiving" to help users manage their mailbox and keep it clutter-free. However, what if, despite your best archiving efforts, your Outlook mailbox size refuses to shrink? This blog delves into this common predicament, exploring the reasons behind it and providing practical solutions to resolve the issue.

The Archiving Conundrum

Archiving in Outlook is a powerful tool, designed to free up space in your mailbox by moving older emails, attachments, and other items to a separate location. However, there's a widespread misconception that archiving these emails will directly reduce the mailbox size as displayed in Outlook. This is not the case. The mailbox size, as indicated by Outlook, remains virtually unaffected even after successful archiving. To understand why this happens, we must first uncover the mechanics of archiving in Outlook.

The Archiving Mechanism

When you use the archiving feature in Outlook, it operates by creating a separate file, usually named "Archive.pst" (for Windows users) or "Outlook Archive" (for Mac users). This file serves as a repository for all the emails and attachments you've chosen to archive. The archived data is effectively moved from your primary mailbox to this external file.

However, the crucial point to note is that Outlook's mailbox size indicator primarily tracks the size of your main mailbox and does not consider the Archive.pst or Outlook Archive file. As a result, even after archiving substantial amounts of data, the mailbox size displayed in Outlook remains relatively constant. This discrepancy can lead to confusion and frustration for users who expect their mailbox size to decrease significantly after archiving.

Solutions to Reduce Mailbox Size

Understanding why your mailbox size remains unchanged after archiving is the first step. To effectively reduce the size of your Outlook mailbox, you need to implement specific strategies and solutions:

1. Empty the "Deleted Items" Folder:

Even deleted items occupy space until they are permanently removed.

2. Compact Your Data File (PST/OST):

You can initiate a compacting process in Outlook to recover space. Go to "File" > "Account Settings" > "Data Files" > select your data file > click "Settings" > navigate to the "Advanced" tab and select "Outlook Data File Settings." Click "Compact Now."

3. Verify Your Archive Settings:

Ensure that your archiving settings are correctly configured. Go to "File" > "Options" > "Advanced" > "AutoArchive Settings" and review the settings to align them with your archiving needs.

4. Manually Move Archived Items:

If your Archive.pst or Outlook Archive file has grown unwieldy, consider manually moving older items to a new PST file. This practice helps distribute the data and reduce the size of your primary mailbox.

5. Remove Unnecessary Attachments:

For emails with large attachments, consider saving the attachments outside of Outlook and removing them from your emails. Bulky attachments can contribute significantly to a bloated mailbox.

6. Explore Cloud-Based Email Services:

Consider transitioning to cloud-based email services that often offer more storage space and simplified archiving features.

7. Regularly Review and Delete Old Emails:

Cultivate the habit of reviewing and deleting emails that have outlived their relevance. This is an essential practice in keeping your mailbox lean and organized.

Direct Solution to Fix Outlook Mailbox Size Issues with ATS OST To PST Converter

Resolving Outlook mailbox size issues is crucial for efficient email management, and ATS OST To PST Converter offers a powerful solution. This tool empowers you to tackle the challenge of a bloated mailbox by efficiently converting OST files to PST format.

By doing so, you can achieve the following benefits:

Reduced Mailbox Size: The conversion process effectively reduces the size of your mailbox, freeing up space for new emails and improved performance.

Efficient Data Management: ATS OST To PST Converter allows you to manage your Outlook data more effectively by organizing it in a PST file. This ensures that your emails are stored in an easily accessible and organized manner.

Data Backup: Converting to PST format serves as a valuable backup, protecting your email data from potential data loss or corruption.

Compatibility: PST files are widely supported across various email clients and platforms, ensuring that your email data remains accessible and secure.

Split Outlook PST file: ATS OST to PST Converter tools to split PST files, which can be especially useful when dealing with large PST files. These tools often provide more flexibility in terms of how you want to split the file, such as by date, size, or specific folders

Conclusion

Import OST to office 365 is very simple that proficient software which can efficiently convert OST to Office 365 without any alteration in the original data. This application export your all items such as inbox, outbox sent-items, deleted-items, drafts, contacts, calendar etc. are Fastly converted into Office365 without any data left behind. With the help of preview option, you can cross check the purity and honesty of the tool before the exportation of OST to Office 365 is done. This setup is also compatible with all the version of MS Outlook such as 98, 2000, 2002, 2003, 2007, 2010, 2013, and 2016. Download the demo version of this tool and convert 30 emails from every folder free of cost.

try to best exchange OST to PST Converter software. visit: 

If do have you an old /corrupted or inaccessible OST file? Are you unable to open your OST files anymore? If yes then you can resolve / fixed all error and these problems by simply converting the OST files into Outlook data file format as PST file or other Different email clients profile formats like MSG, EML, EMLX, MBOX, and HTML formats. In such circumstances; OST to PST file conversion is the only possible solution to get back your data.  

                 In case to corrupt/ damaged or deleted/ permanently deleted Exchange Outlook OST file or email items to recover OST file data. I would like to be suggesting for you used OST to PST conversion tool. This tool is easily repair corrupt OST file and recovers OST mails items and Convert OST to PST file. 

Important key feature of OST to PST Software

- Faster OST to PST Conversion with Time Saving Tool

- Restore all properties: such as: To, Bcc, cc, time, subject, images, date, & all attachments etc.

- Restore deleted/ permanently deleted OST emails items

-  Complete conversion of .OST mailbox contents Emails, Attachments, Calendar, Contacts, Notes, journals and all mailbox elements.

- Export the converted OST files in PST, EML, MSG, EMLX, MBOX and HTML file format

More information visit link: https://gallery.technet.microsoft.com/free-OST-to-PST-Converter-a51fc20c