Log On To MS Exchange Mailboxes & SharePoint Sites Automatically

CodeTwo Autologon is a FREE Windows utility that automatically fills in user's credentials every time they access a given SharePoint site or Exchange mailbox. Supports multiple accounts, and works from outside domain profiles. I tested it with links to files in Office365 SharePoint Online and it worked fine.  Requires Internet Explorer and/or Microsoft Outlook.
See: http://www.codetwo.com/freeware/autologon/