Emails you have received or sent in the past, may contain vital information. Being able to quickly retrieve data present in old messages will be crucial for your functioning.

This email archive should be arranged in a set of hierarchical folders. If you devise a well thought-out structure, that structure can be kept year after year. Microsoft Outlook outperforms all other email clients in this respect. The flat structure offered by Google GMail does not provide this necessary structure, however fast their email search machine is claimed to be.

Keeping old emails

Given the very low price of disk space these days there is no need whatsoever to delete any old emails out of economy reasons. You can – and should – keep all your old emails. Organize them in hierarchical folders. Many modern email clients offer this facility.

Archiving formats

There is no standard file format for the archiving of email messages. The best type depends very much on the way your email client saves your email messages.

Ideal format

The ideal saving format – at least in my opinion – would be to have for each email message a separate directory containing the full email message (including all message headers, but stripped from its attachments) as a single ASCII file and in addition containing the attached files accompanying it as separate files.

My ideal has as a possible problem that it might be somewhat slower to find a particular old email message or one of its attachments. But the good thing is that the email archive remains readable forever and the readability is not connected to any proprietary file format that might become obsolete, of some commercial email client. Eudora (an email client that is sadly no longer being developed) has a way of saving messages that comes a long way towards my ideal.

Proprietary file formats

Email messages, including their attachments, are sent around the world as ASCII files. The first thing commercial companies do when developing email software is to turn these universally readable ASCII email messages into a proprietary object file format that can only be read and maintained with proprietary software from this one and only company. It is capitalism, all the way.