Increasing the OST file size in Outlook can be a challenge, especially since the limit for OST files is up to 50 GB. As you download more data from the mail server, the OST file can grow significantly, potentially leading to file errors or space issues. To address these problems, using an OST recovery tool can be very effective. This tool not only helps in managing large OST files but also allows you to convert them to a more manageable PST format.

By using the eSoftTools OST to PST Converter tool, you can convert your oversized or problematic OST files into PST format, which is better suited for handling large volumes of data. This conversion helps alleviate issues related to file size and reduces the risk of file errors. Additionally, many OST recovery tools offer a free trial version, allowing you to test the software and ensure it meets your needs before making a purchase.

More info - Increase OST File Size in Outlook 2021, 2019, 2016, 2013, 2010