There are times when you just need to check or retrieve something from an old PST file, but installing Outlook seems like too much work. The MS Outlook Help PST File Viewer makes it easy to do that without Outlook. It works even with PST files that aren't linked to an Outlook profile called "orphaned” files and lets you browse everything in them. The tool displays all kinds of mailbox items, including calendar items and tasks, in a neat and understandable tree view. You can scroll through folders and read messages without making any changes to the original file.