Entourage is the email app that comes with Microsoft Office for Mac. Some people prefer it to Apple's Mail. Others (like us) use it because IT departments insist on it, typically to work with a Microsoft Exchange server, although Mail also now supports Exchange.

Entourage's problem is that it stores mailboxes in a single file called 'Database'. Most people hang on to emails as a record, and it's not ideal to have all your eggs in one large basket.

Any file that's constantly read and written is liable to corruption. And if you include it in your backups using Mac OS X's Time Machine, that's a big chunk of data to update.

Entourage Time Machine from Softhing aims to help. With one click, it copies all your messages to a set of XML files. You can then browse and search these in a viewer.

It's simple and it works, but not perfectly. Currently only POP accounts are handled. Archiving around 50,000 messages, we found the initial backup glitchy.

Incremental backups are quick, but they can't be automated. The viewer only shows plain text, so HTML emails are garbled. The developers claim searching emails is faster than with Entourage.

But entering search terms often gave us an error, and when it worked it was slow – as was folder switching. The app's not quite there yet, but it has some interesting potential.

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