Have you had trouble viewing emails saved in mbox extension? The easy way is to convert the mbox files to eml files, since eml is a widely used file format and Outlook could open it. (I am using Microsoft Outlook 2010 as my email client, maybe there are other simpler options.) Although IMAPSize is mainly a IMAP mail accounts manager, it contains a very useful tool that converts mbox files to eml files and vice versa. It also maintains the folder hierarchy by recognizing dots as folder separators. Another way of viewing mbox mails is using MailStore Home . Basically, it archives your emails to a local directory, and let you view the emails. Besides eml and mbox file extensions, MailStore Home directly archives emails from Outlook, Windows Mail, Thunderbird, and Google Mail, to name a few. Comparing to IMAPSize, MailStore Home does not maintain the folder hierarchy while archiving mbox files, i.e. you have to move the emails to manually-created sub-folders. Why did I mention MailStor...