Looking for a tool to open PST files when Outlook isn’t available? The MSOutlookHelp PST Viewer makes it easy to read all your mailbox content without installing the full Outlook program. It supports opening PST files that aren’t linked to any Outlook profile, so old or orphaned files are no problem. The viewer doesn’t change or damage your data it simply shows it exactly as it is. Additionally, it’s light on system resources, so even slower computers can open big PST archives without freezing.