Executives who work on Outlook for work communication, must be aware of OST (Offline Storage Table) and PST (Personal Storage Table) files. OST files are tied with mail servers. They are used with Microsoft Exchange and Outlook 365 accounts in cached Exchange mode. Using .ost files, a user can send email messages even without internet connectivity. Let’s understand the other file format (.pst). Touted as the personal folder, the PST (Personal Storage Table) files are used for storing mailbox data on the local device. They are widely used for archiving purpose. In nutshell, both these file formats ensure the seamless functioning of the email client.
Certain scenarios demand import of Outlook data file (.ost) to PST format. Checkout this guide to know about some manual methods for such conversion. The guide will also clear up the haze from an Online OST Converter. This guide post titled “How to Convert OST to PST Free Online in Just a Few Clicks,” will shed light on every aspect associated with such conversion. In addition to this, the post will also uncover a free OST to PST converter tool.

Understanding OST to PST Conversion?
Outlook data file (.ost) is highly encrypted. It is linked to a specific profile. In some cases, this data file becomes orphaned due to technical reasons. To access the mailbox folder when .ost file is inaccessible, the user needs to convert it into .pst format. Some common scenarios where such conversion becomes necessary include the following:
- Frequent error messages: When the user experience error messages like “abc123.OST is not an Outlook data file” etc., it becomes essential to import data file (.ost) to portable .pst format.
- Exchange account deletion: If the user accidently deleted or removed the Exchange account, conversion of .ost file to .pst format becomes essential.
- Accessing .ost folders on a different device: If the user requires to access .ost file folders on a different device, such conversion becomes necessary.
- Orphaned or inaccessible files: If the user requires to recover mailbox folders from inaccessible or orphaned .ost files, such conversion becomes mandatory.
- Archiving purpose: Such conversion is also required in case of creating backups for the offline storage.
- Server issues: If the user needs to access email messages in the event of server corruption, or downtime, it can be done by converting the data file (.ost) to .pst format.
- Data migration: Such conversion is required when the user is shifting to a new email client.
Methods of Importing Folders from OST to PST:
After clearing up the haze from scenarios demanding conversion, let’s move on to explore methods to transfer Outlook data file (.ost) to .pst file format. Some common ways for such action are discussed below:
1. Using Outlook’s Import/Export Feature: This is one of the common methods used for such conversion. The step-by-step guide is discussed below:
- Browse Microsoft Outlook.
- Open the top menu bar and click Files.
- Go to “Open & Export.”
- After this hit on the Import/Export.
- Press Export to a file. Click Next to proceed.
- Select Outlook Data File (*.pst) from the list of options, then click Next.
- After this select the folders you need to convert. Then click Next.
- Choose the folder where you want to save the PST file, then click Finish
2. Drag-and-Drop Method: This manual approach is recommended when the transfer, import of a few folders is involved. Follow below instructions:
- Create a blank PST data file.
- Selection of targeted mailbox folders.
- Drop such selected folders to the newly created PST file.
3. Utilize a Specialized Tool: The above methods are not suitable for large-scale transfers. They might not be able to convert Outlook data files (.ost) that are heavily damaged or separated from an active profile. In such a case, we need any specialized third-party tool to perform such task. Such OST to PST converter is capable of converting even an inaccessible or orphaned files.
Limitations of the above methods:
Manual Methods | OST to PST Converter Software |
Require a degree of technical expertise | Comes with a cost |
Time-consuming and complex procedures | Require your device resources (RAM, CPU, storage) |
May not work on inaccessible or orphaned files | May create compatibility issues |
Decoding OST to PST Converter?
Some users query about any other smart way to convert OST files to PST format without installing any third-party software. Other Outlook users also enquire about any free OST to PST converter. The answer to this query is yes. We can use any Online OST Converter for this task. In fact, it is the smartest and easiest way. Its procedure involves following three steps:
- Upload the .ost file
- Convert it into PST format
- Download the converted data file (.pst)
Benefits of Using an Online OST Converter:
- No need of installing Outlook
- No dependency on system resources (RAM, CPU, etc.)
- Prompts conversion even when the Exchange Server is not available
- Obedience to customer privacy regulations
- Simple process, apt for non-technical users
- No software download and installation needed
- Maintains hierarchy of the folder
Conclusion:
In the above guide titled “How to Convert OST to PST Free Online in Just a Few Clicks” we have explored two manual methods viz.- Import/ Export Wizard and the Drag & Drop method. But these methods are not recommended for bulk conversion. We have also discussed about third-party converter software. But many Outlook users demand quick conversion without installing any software. The answer for their query lies in Online OST Converter. We have also explored multiple benefits of online conversion that range from saving system resources and disk space to compliance to customer privacy regulations.