Easy way to combine PST files with PST Merge Program. The application is capable enough to merge any large PST file without harming any element like email attributes (to, cc, bcc, sent, from, etc.) and attachments. The program has an advanced feature that allows dismissing blank folders from the merging process. If you choose the manual method to join multiple PST files, there are chances that you might face issues like data loss, changes in the folder structure, etc.