Take a look at MailStore Home for offline backup. The personal version is free. http://www.mailstore.com/en/mailstore-home.aspx http://www.mailstore.com/en/ma

Take a look at MailStore Home for offline backup. The personal version is free. http://www.mailstore.com/en/mailstore-home.aspx http://www.mailstore.com/en/mailstore-home.aspx It can work with a variety of mail sources, including gmail. It also builds a full text index so that you can search offline. I have no affiliation with the company but I am using it to backup my gmail.