When archiving an old PST, reviewing the attachments is just as important as checking the email messages. A mailbox may contain PDFs, spreadsheets, images, contracts, or other documents that should not be overlooked during the archive process. Opening everything manually in Outlook can become difficult when the PST contains thousands of messages.

I would first check whether the PST can be accessed independently and whether the folder structure is still readable. It is also useful to verify attachments by sender, subject, or date so that important messages can be located without going through the entire archive.

For this type of review, SysInfo PST Viewer  provides a practical option because it can open PST files without requiring Microsoft Outlook. It lets users preview email bodies, attachments, headers, MIME data, contacts, calendars, tasks, and other mailbox items. Its search filters can narrow emails by sender, recipient, subject, date range, and attachment status.

Another useful point is that the viewer works in read-only mode by default, so the original PST is not intended to be modified during scanning or viewing. It can also handle multiple PST/OST files and provides selective export options when specific messages or attachments need to be preserved separately.

For large archives, I would recommend reviewing the folder hierarchy first, identifying attachment-heavy folders, and then exporting only the information required for long-term storage. This makes the archive easier to manage while reducing unnecessary data.