GainTools Merge PST Tool is for people who use Outlook and need to combine several PST files into one smooth data file. It combines emails, contacts, calendars, tasks, and attachments quickly and without changing the layout or data integrity of the original files. You can easily merge PST files of any size and type, even ones that are password-protected. It has an easy-to-use UI that makes it easy for both novices and experts to use. This application works with Outlook and Windows OS. It's great for putting all of your PST files in one place so you can easily find them.