Old MSG emails are not easy to manage when there are many files. I faced the same issue while saving old Outlook emails as PDFs. Manually printing was possible for many emails, but this process turned into being tedious and complicated when there were attachments.
In this situation, Softaken MSG to PDF Converter should be mentioned. The software allows the user to load MSG files or even an entire folder and convert them to PDFs. The useful part is that attachments are not skipped. It also keeps basic email details like sender, date, subject, and message content readable.
My suggestion is simple: first try a few MSG files, check the PDF output and attachments, then convert the full folder. Always keep a backup of the original MSG files before starting.