Converting EML files to PST on Windows is required when you want to access emails in Microsoft Outlook. EML files are individual email messages, while PST stores complete mailboxes. You can use Advik EML to PST converter to add multiple EML files, choose PST as the output format, and convert them in one process. This method saves time, preserves attachments, and keeps email properties intact. Manual drag-and-drop works only for a few files and is not reliable for bulk conversion.