For the optimum OST to PDF conversion, you can use the MigrateEmails OST to PST Converter Tool makes it easier for you to export OST to PDF file format in bulk. Providing you with multiple destination file formats and email clients, the tool is a one-stop solution to meet all your conversion needs for Outlook data file. Giving you the new features to configure the output file as you want.

Follow the below instructions to export Outlook OST into PDF file format.
1. Download and install the MigrateEmails OST to PST Converter. Install and run it in administrator mode.
2. Click the Browse button and choose your desired file. Click the Open button to insert the file.
3. Then choose the desired items from the mailbox preview. Click the Next button.
4. Now click on PDF in the Save/Backup/Migrate As field.
5. Select the remaining tool options according to your requirement.
6. Finally, click on the Convert button for initiating the file conversion.

Alternatively, To convert OST to PDF manually, open the OST file in Microsoft Outlook (offline, Deregister Exchange Account). Select the selected emails, then go to File > Save As and save them individually or in batches as PDF files.

This process takes a while as each mail needs to be separately saved and batch PDF export through Outlook is not possible. Also, if the Exchange account goes offline, OST files are not accessible anymore. Additionally, attachments, email styling, and even metadata cannot be copied reliably in all cases.

Read More: https://www.cloudemailmigration.com/blog/convert-ost-to-pdf/