AutoArchive is a handy feature to increase the overall performance of Outlook 2010. it sends all the old/in-active items (mails, tasks, calendar items, notes, etc) to Archive.pst file, so you can use them anytime in the future. This post covers how to create to use AutoArchive option.
To begin, under Folder tab, click AutoArchive Settings.
Here you can configure Auto Archive settings, such as setting time duration for cleaning items, and moving old items to default archive items. Once configured, click OK to apply the settings. It will start sending the old items to Archive.pst according to the user-defined configurations.