The process to move email from account to account may seem simple and easy to do but unfortunately it isn’t. This is because there is no universal standard for email messages and contacts.
Universal Standard
A universal standard for email messages and contacts would be nice because it would make the export feature of your email client compatible with the import feature on all of the other email clients. Thunderbird would be able to move to Entourage, Mac Mail could be moved to Outlook. This would make the task to move email and contacts simpler and easier. So why didn’t someone make up a standard?
The Problem
Well, ‘universal standards’ have come out but no one follows them. Email clients are created by companies that want a profit. If all email clients were compatible with a universal standard, then you could move your accounts between clients easily and find the BEST email client for yourself. This does not benefit the company that spent umpteen billion dollars developing an email client that everyone moves away from. Email clients need you to stick with them. The best method to do this is to make ‘proprietary’ formats so that it is not simple for you to transfer your account. Here’s the technical details:
Technical Details of the Problem
Email messages are stored in several different formats by different email clients. Outlook and Outlook for Mac stores email messages within a PST or OLM file. Mac Mail, Windows Live mail and Thunderbird use the MBX format. There are a number of other formats out there, as well. These formats are not compatible with each other. Some email clients attempt to provide the ability to import other email types but usually they aren’t too dependable.
Email clients typically export Contacts as a .VCF or .CSV file. Luckily, most email clients can import either format – now why don’t they do the same for email??
Solution
All email clients should adopt a Universal Standard for emails and contacts. This would provide a simple method to move email and contacts between programs. If all clients use the same email standard then we can move on from compatibility issues to email client features. We could start improving email clients and make them the amazing tools they are destined to be.

Office for Mac 2011. The new release will no longer incorporate the Entourage program. Most people are very, very happy for this change.