You can view PST file attachments without opening the file in Outlook by using a dedicated PST Viewer. MacSonik PST Viewer  lets you load a PST file and preview emails along with their attachments, contacts, calendars, and other mailbox data.
To view attachments, add the PST file, expand the mailbox folder, select the required email, and open its Attachments section. You can also use attachment-based filtering to quickly find emails containing attachments. The tool provides options to keep, extract, convert, or exclude attachments when exporting the data.