If you are still running Exchange Server 2003, you then need to fast track your workplace 365 migration, because Exchange 2003 stopped being supported by Microsoft in 2014. What's more, most Exchange Server 2003 systems are running on Windows Server 2003 which will also no longer be supported by Microsoft after June 2015. Both of these events mean your system will undoubtedly be increasingly available to external hacker attacks as security breaches are no longer being fixed by Windows updates.

In addition, if you don't have moved your server to a virtual environment sometime during the last few years, it is extremely likely that your physical file server is also out of warranty, running slowly, nearing its disk capacity and starting to suffer reliability issues.

Migration from Exchange 2003 to Office 365 can still be safely done, however there is often an extra problem to be overcome concerning Microsoft Outlook. Many organizations that are running Exchange 2003 may also be running Office 2003. The good news is that moving to Office 365 presents a great possibility to also replace Office 2003 by choosing an Office 365 plan which includes Office 2013 - including the Office 365 Business Premium plan.

The bad news is you've got a chicken and egg situation because Office 2003 in general - and Outlook 2003 in particular - can not work with Office 365. This means that during the migration process you have to decide between upgrading your email system first, and then not being able to access it until you've updated all of the computers to a later version of Office (at least office 2007). Or, you upgrade all of the computers to a newer version of Office first, and do the migration of Exchange Server to Office 365.

Whichever method you choose, you will have a period of time when users are stuck in no man's land - they don't be able to access their email server from their version of Outlook. So a decision need to be made - is it far better upgrade Office first, or is it best to upgrade the e-mail server first? more info shows that it's best in every situation to upgrade to Office 365 first and upgrade Office 2003 users to Office 2013. Here's two hypothetical examples to prove this point:

Company A has 20 staff with 19 users running Outlook 2010 on the computers and with only one user running Outlook 2003. It might be best to migrate the email server to Office 365 first, because only the main one user won't be in a position to access the brand new email server until their version of Office gets upgraded. And it should take only one hour or so to get that user's computer upgraded to Office 2013.

Company B also offers 20 staff, but in their case 19 users are on Office 2003 and only one is on say Office 2010. At first glance this seems like an issue - if the Exchange 2003 Server is migrated to Office 365 first then your 19 staff won't be able to access their emails before computers have Office 2013 installed. And conversely, if the 19 computers are updated to Office 2013 first, they won't manage to access their emails before Office 365 migration process has been completed. Fortunately, in this instance there is a very good interim solution - users could make usage of OWA (Outlook Web Access) to gain access to their emails via the browser until their computers are updated to Office 2013. Indeed, it will be possible for them to now have access to Office 365 email on a variety of smartphones and tablets they may curently have like iPhones, iPads, Windows mobile devices and Android devices.

Performing migrations to Office 365 from later versions of Exchange are a lot better to action, but with a well-designed scoping plan that considers the implications of old versions of Office, the Exchange 2003 migration process can still be performed in a timely and cost-effective fashion.

It may well be that the ultimate way to assure your organization of an effective Office 365 migration from Exchange 2003 is to use the services of a Microsoft Partner which has Office 365 certifications and real-world experience in performing Office 365 migrations.