Can the Microsoft OST to PST Converter handle large OST files?

[chandankapat]

You would require a third tool like Stellar Converter for OST. One of the main feature of the tool is to convert large, inaccessible and orphaned OST file into PST with 100% precision. This tool also helps you to convert multiple OST files into PST files in one go with its batch file conversion feature. It also helps you to auto locate your configured OST file to convert to PST file and also helps in converting encrypted OST file to PST file which is impossible in manual method. This tool also helps to export converted OST file to Office 365 saving your time. If the converted OST file is too large then this tool is also capable of compressing or splitting the PST file saving you your local space. This tool is compatible with various windows versions and Outlook versions as well. Once the OST file is scanned you can easily preview it to check if all your mailbox data are present properly.

So, by this you can get that for converting large OST file you would require a third party OST to PST converter.

[henrypit74]

Yes the Microsoft OST to PST Converter can handle large OST files but with some limitations. In Outlook the built-in export feature allows users to convert OST to PST but it may struggle with large files due to performance issues and corruption risks. For smoother conversion of large OST files it is recommended to use professional tool like WholeClear OST to PST Converter which are designed for handling large OST files without data loss. It includes features like selective export and enhanced speed making them more suitable for enterprise-level OST file conversion tasks.

[jackdanie]

Microsoft doesn’t provide a built-in OST to PST Converter. The only native option is Outlook’s Import/Export feature, which works only if the OST is healthy and linked to its original profile. For very large OST files, this method often fails or takes a long time.

To handle large or orphaned OST files, a professional tool like BLR OST Converter is recommended. It’s designed to process oversized OSTs smoothly, without data loss, and preserves emails, attachments, contacts, and calendars.

In short, Outlook alone struggles with large OSTs—specialized converters are the safer choice.